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Medical devices and US 220V electrics

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  Medical devices and US 220V electrics RBlack <news@rblack01.plus.com> - 2017-05-25 13:05 +0100
    Re: Medical devices and US 220V electrics Winfield Hill <hill@rowland.harvard.edu> - 2017-05-25 05:55 -0700
    Re: Medical devices and US 220V electrics upsidedown@downunder.com - 2017-05-25 17:26 +0300
      Re: Medical devices and US 220V electrics Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-25 10:27 -0400
        Re: Medical devices and US 220V electrics George Herold <gherold@teachspin.com> - 2017-05-25 08:39 -0700
          Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-25 12:40 -0400
      Re: Medical devices and US 220V electrics Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-25 15:03 +0000
        Re: Medical devices and US 220V electrics upsidedown@downunder.com - 2017-05-25 20:09 +0300
      Re: Medical devices and US 220V electrics RBlack <news@rblack01.plus.com> - 2017-05-25 16:56 +0100
        Re: Medical devices and US 220V electrics Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-25 16:42 +0000
        Re: Medical devices and US 220V electrics upsidedown@downunder.com - 2017-05-25 20:38 +0300
        Re: Medical devices and US 220V electrics whit3rd <whit3rd@gmail.com> - 2017-05-25 10:48 -0700
        Re: Medical devices and US 220V electrics Neon John <no@never.com> - 2017-05-28 15:48 -0400
        Re: Medical devices and US 220V electrics rickman <gnuarm@gmail.com> - 2017-05-29 01:08 -0400
      Re: Medical devices and US 220V electrics Cursitor Doom <curd@notformail.com> - 2017-05-25 17:51 +0000
        Re: Medical devices and US 220V electrics upsidedown@downunder.com - 2017-05-25 21:25 +0300
      Re: Medical devices and US 220V electrics "Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com> - 2017-05-26 11:55 -0400
        Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-26 17:38 -0400
          Re: Medical devices and US 220V electrics "Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com> - 2017-05-26 20:32 -0400
            Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-26 22:20 -0400
              Re: Medical devices and US 220V electrics "Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com> - 2017-05-27 00:33 -0400
                Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-27 09:37 -0400
    Re: Medical devices and US 220V electrics legg <legg@nospam.magma.ca> - 2017-05-25 12:07 -0400
      Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-25 12:49 -0400
        Re: Medical devices and US 220V electrics Neon John <no@never.com> - 2017-05-28 15:56 -0400
          Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-28 16:59 -0400
        Re: Medical devices and US 220V electrics upsidedown@downunder.com - 2017-05-30 12:37 +0300
          Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-30 17:41 -0400
      Re: Medical devices and US 220V electrics gregz <zekor@comcast.net> - 2017-05-30 06:58 +0000
    Re: Medical devices and US 220V electrics rickman <gnuarm@gmail.com> - 2017-05-25 12:15 -0400
      Re: Medical devices and US 220V electrics Jon Elson <jmelson@wustl.edu> - 2017-05-25 15:07 -0500
        Re: Medical devices and US 220V electrics John Larkin <jjlarkin@highland_snip_technology.com> - 2017-05-25 13:14 -0700
          Re: Medical devices and US 220V electrics Jon Elson <jmelson@wustl.edu> - 2017-05-25 16:34 -0500
        Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-25 18:47 -0400
          Re: Medical devices and US 220V electrics Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2017-05-27 01:46 +0200
            Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-26 19:53 -0400
              Re: Medical devices and US 220V electrics Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2017-05-27 02:05 +0200
                Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-26 22:21 -0400
                  Re: Medical devices and US 220V electrics Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2017-05-27 04:25 +0200
                    Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-26 22:33 -0400
                      Re: Medical devices and US 220V electrics Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2017-05-27 21:48 +0200
    Re: Medical devices and US 220V electrics Don Y <blockedofcourse@foo.invalid> - 2017-05-25 11:20 -0700
    Re: Medical devices and US 220V electrics Jon Elson <jmelson@wustl.edu> - 2017-05-25 14:57 -0500
      Re: Medical devices and US 220V electrics RBlack <news@rblack01.plus.com> - 2017-05-26 12:17 +0100
        Re: Medical devices and US 220V electrics tabbypurr@gmail.com - 2017-05-26 04:53 -0700
        Re: Medical devices and US 220V electrics Phil Allison <pallison49@gmail.com> - 2017-05-26 06:00 -0700
        Re: Medical devices and US 220V electrics rickman <gnuarm@gmail.com> - 2017-05-26 12:05 -0400
        Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-26 17:51 -0400
          Re: Medical devices and US 220V electrics George Herold <gherold@teachspin.com> - 2017-05-26 17:54 -0700
            Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-26 22:24 -0400
        Re: Medical devices and US 220V electrics upsidedown@downunder.com - 2017-05-27 00:52 +0300
          Re: Medical devices and US 220V electrics Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-05-26 15:39 -0700
        Re: Medical devices and US 220V electrics Neon John <no@never.com> - 2017-05-28 16:34 -0400
          Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-28 17:26 -0400
            Re: Medical devices and US 220V electrics Neon John <no@never.com> - 2017-05-29 12:12 -0400
              Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-29 14:26 -0400
    Re: Medical devices and US 220V electrics Tim Wescott <tim@seemywebsite.really> - 2017-05-29 00:08 -0500
    Re: Medical devices and US 220V electrics David Lesher <wb8foz@panix.com> - 2017-05-29 20:24 +0000
      Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-29 16:37 -0400
        Re: Medical devices and US 220V electrics David Lesher <wb8foz@panix.com> - 2017-05-30 16:33 +0000
          Re: Medical devices and US 220V electrics Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-05-30 09:46 -0700
          Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-30 17:45 -0400
            Re: Medical devices and US 220V electrics David Lesher <wb8foz@panix.com> - 2017-05-31 03:31 +0000
              Re: Medical devices and US 220V electrics krw@notreal.com - 2017-05-31 17:58 -0400
                Re: Medical devices and US 220V electrics Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-06-01 07:54 +0000
                  Re: Medical devices and US 220V electrics upsidedown@downunder.com - 2017-06-01 12:49 +0300
                    Re: Medical devices and US 220V electrics Neon John <no@never.com> - 2017-06-01 10:28 -0400
                      Re: Medical devices and US 220V electrics Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-06-01 14:45 +0000
                      Re: Medical devices and US 220V electrics Neon John <no@never.com> - 2017-06-01 18:47 -0400
                        Re: Medical devices and US 220V electrics Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-06-01 15:57 -0700
                          Re: Medical devices and US 220V electrics Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-06-02 07:21 +0000
                        Re: Medical devices and US 220V electrics krw@notreal.com - 2017-06-01 18:59 -0400
                Re: Medical devices and US 220V electrics David Lesher <wb8foz@panix.com> - 2017-06-03 14:00 +0000
                  Re: Medical devices and US 220V electrics krw@notreal.com - 2017-06-03 11:19 -0400
      Re: Medical devices and US 220V electrics upsidedown@downunder.com - 2017-05-30 01:16 +0300
        Re: Medical devices and US 220V electrics tabbypurr@gmail.com - 2017-05-29 22:31 -0700
          Re: Medical devices and US 220V electrics Phil Allison <pallison49@gmail.com> - 2017-05-29 23:06 -0700
            Re: Medical devices and US 220V electrics tabbypurr@gmail.com - 2017-05-29 23:25 -0700
              Re: Medical devices and US 220V electrics Phil Allison <pallison49@gmail.com> - 2017-05-29 23:39 -0700
                Re: Medical devices and US 220V electrics tabbypurr@gmail.com - 2017-05-30 00:19 -0700
              Re: Medical devices and US 220V electrics rickman <gnuarm@gmail.com> - 2017-05-30 10:40 -0400
      Re: Medical devices and US 220V electrics rickman <gnuarm@gmail.com> - 2017-05-30 10:37 -0400
    Re: Medical devices and US 220V electrics Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-05-30 16:58 -0700
      Re: Medical devices and US 220V electrics Don Y <blockedofcourse@foo.invalid> - 2017-05-30 22:15 -0700
        Re: Medical devices and US 220V electrics Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-05-31 07:38 -0700
      Re: Medical devices and US 220V electrics Don Kuenz <g@crcomp.net> - 2017-05-31 14:05 +0000
        Re: Medical devices and US 220V electrics Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-05-31 07:40 -0700
        Re: Medical devices and US 220V electrics Don Y <blockedofcourse@foo.invalid> - 2017-05-31 09:37 -0700

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#461639 — Medical devices and US 220V electrics

Hi,

We are working on a medical product, which will draw about 3 kW from the 
mains.  This is new territory for us, all our previous products were a 
few hundred watts max so an off-the-shelf auto-ranging PSU with a 
suitable IEC lead was OK for any country in the world.

3 kW is OK for a standard outlet in 220V countries, but for North 
America, Japan etc we are over the limit for a standard 110V outlet.

I only know as much about US electrical installations as I've read, a 
bit of Googling suggests the product will need a NEMA 6-15 220V outlet.  
But how common are these in hospitals?  Anybody have any experience of 
this stuff?

It has been suggested (not by me I hasten to add) that we split the 
loads within the product up and give it two 110V inlets, to get around 
the customer having to install a 'special' outlet for it.  This sounds 
like a Really Bad Idea and a regulatory nightmare to me, so if 220V 
outlets are commonly available anyway I can shoot it down before it gets 
too far.

TIA

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#461646

RBlack wrote...
>
> We are working on a medical product, which will draw
> about 3 kW from the mains.  

 You need to work really hard to get that down to 1.5kW.


-- 
 Thanks,
    - Win

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#461657

On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
wrote:

>We are working on a medical product, which will draw about 3 kW from the 
>mains.  This is new territory for us, all our previous products were a 
>few hundred watts max so an off-the-shelf auto-ranging PSU with a 
>suitable IEC lead was OK for any country in the world.

Is this peak or average ?
Is it 3 kW or 3 kVA ? What power factor ?

>3 kW is OK for a standard outlet in 220V countries, but for North 
>America, Japan etc we are over the limit for a standard 110V outlet.

It is not OK for 220-240 V outlets with 10 A fuses. You would have to
install a dedicated 16 A outlet.

Any additional loads on the same fuse might eventually blow the fuse,
a situation which is not appreciated in a hospital environment.

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#461658

On 05/25/2017 10:26 AM, upsidedown@downunder.com wrote:
> On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
> wrote:
> 
>> We are working on a medical product, which will draw about 3 kW from the 
>> mains.  This is new territory for us, all our previous products were a 
>> few hundred watts max so an off-the-shelf auto-ranging PSU with a 
>> suitable IEC lead was OK for any country in the world.
> 
> Is this peak or average ?
> Is it 3 kW or 3 kVA ? What power factor ?
> 
>> 3 kW is OK for a standard outlet in 220V countries, but for North 
>> America, Japan etc we are over the limit for a standard 110V outlet.
> 
> It is not OK for 220-240 V outlets with 10 A fuses. You would have to
> install a dedicated 16 A outlet.
> 
> Any additional loads on the same fuse might eventually blow the fuse,
> a situation which is not appreciated in a hospital environment.
> 

Not to mention what it'll do to the room temperature.  What is it, a
defibrillator for whales?

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

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#461669

On Thursday, May 25, 2017 at 10:27:50 AM UTC-4, Phil Hobbs wrote:
> On 05/25/2017 10:26 AM, upsidedown@downunder.com wrote:
> > On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
> > wrote:
> > 
> >> We are working on a medical product, which will draw about 3 kW from the 
> >> mains.  This is new territory for us, all our previous products were a 
> >> few hundred watts max so an off-the-shelf auto-ranging PSU with a 
> >> suitable IEC lead was OK for any country in the world.
> > 
> > Is this peak or average ?
> > Is it 3 kW or 3 kVA ? What power factor ?
> > 
> >> 3 kW is OK for a standard outlet in 220V countries, but for North 
> >> America, Japan etc we are over the limit for a standard 110V outlet.
> > 
> > It is not OK for 220-240 V outlets with 10 A fuses. You would have to
> > install a dedicated 16 A outlet.
> > 
> > Any additional loads on the same fuse might eventually blow the fuse,
> > a situation which is not appreciated in a hospital environment.
> > 
> 
> Not to mention what it'll do to the room temperature.  What is it, a
> defibrillator for whales?
I'd welcome a little more heat in hospital rooms.  I was in one a week 
or two ago, they keep those things too cold for my blood.  

George H. 
> 
> Cheers
> 
> Phil Hobbs
> 
> -- 
> Dr Philip C D Hobbs
> Principal Consultant
> ElectroOptical Innovations LLC
> Optics, Electro-optics, Photonics, Analog Electronics
> 
> 160 North State Road #203
> Briarcliff Manor NY 10510
> 
> hobbs at electrooptical dot net
> http://electrooptical.net

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#461679

On Thu, 25 May 2017 08:39:27 -0700 (PDT), George Herold
<gherold@teachspin.com> wrote:

>On Thursday, May 25, 2017 at 10:27:50 AM UTC-4, Phil Hobbs wrote:
>> On 05/25/2017 10:26 AM, upsidedown@downunder.com wrote:
>> > On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
>> > wrote:
>> > 
>> >> We are working on a medical product, which will draw about 3 kW from the 
>> >> mains.  This is new territory for us, all our previous products were a 
>> >> few hundred watts max so an off-the-shelf auto-ranging PSU with a 
>> >> suitable IEC lead was OK for any country in the world.
>> > 
>> > Is this peak or average ?
>> > Is it 3 kW or 3 kVA ? What power factor ?
>> > 
>> >> 3 kW is OK for a standard outlet in 220V countries, but for North 
>> >> America, Japan etc we are over the limit for a standard 110V outlet.
>> > 
>> > It is not OK for 220-240 V outlets with 10 A fuses. You would have to
>> > install a dedicated 16 A outlet.
>> > 
>> > Any additional loads on the same fuse might eventually blow the fuse,
>> > a situation which is not appreciated in a hospital environment.
>> > 
>> 
>> Not to mention what it'll do to the room temperature.  What is it, a
>> defibrillator for whales?
>I'd welcome a little more heat in hospital rooms.  I was in one a week 
>or two ago, they keep those things too cold for my blood.  

That's why they invented blankets.

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#461661

On a sunny day (Thu, 25 May 2017 17:26:01 +0300) it happened
upsidedown@downunder.com wrote in
<gppdic1713mfpmmvv5466qgg74l8fr1k8r@4ax.com>:

>On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
>wrote:
>
>>We are working on a medical product, which will draw about 3 kW from the 
>>mains.  This is new territory for us, all our previous products were a 
>>few hundred watts max so an off-the-shelf auto-ranging PSU with a 
>>suitable IEC lead was OK for any country in the world.
>
>Is this peak or average ?
>Is it 3 kW or 3 kVA ? What power factor ?
>
>>3 kW is OK for a standard outlet in 220V countries, but for North 
>>America, Japan etc we are over the limit for a standard 110V outlet.
>
>It is not OK for 220-240 V outlets with 10 A fuses. You would have to
>install a dedicated 16 A outlet.

It is 230V here these days.
You could 3 phase power.
Then you can have smaller filter caps too ;-)

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#461685

On Thu, 25 May 2017 15:03:48 GMT, Jan Panteltje
<pNa0nStpealmtje@yahoo.com> wrote:

>On a sunny day (Thu, 25 May 2017 17:26:01 +0300) it happened
>upsidedown@downunder.com wrote in
><gppdic1713mfpmmvv5466qgg74l8fr1k8r@4ax.com>:
>
>>On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
>>wrote:
>>
>>>We are working on a medical product, which will draw about 3 kW from the 
>>>mains.  This is new territory for us, all our previous products were a 
>>>few hundred watts max so an off-the-shelf auto-ranging PSU with a 
>>>suitable IEC lead was OK for any country in the world.
>>
>>Is this peak or average ?
>>Is it 3 kW or 3 kVA ? What power factor ?
>>
>>>3 kW is OK for a standard outlet in 220V countries, but for North 
>>>America, Japan etc we are over the limit for a standard 110V outlet.
>>
>>It is not OK for 220-240 V outlets with 10 A fuses. You would have to
>>install a dedicated 16 A outlet.
>
>It is 230V here these days.

The _nominal_ voltage for _EU_ countries is 230 V. In order to get
both 220 and 240 V counties, they just widened the voltage tolerances
of 230 V so that it included both 220 and 240 V with tolerances.

With a SMPS, the current drawn will increase at 220 V and below,
causing a lot more stress to the fuse.

>You could 3 phase power.

Absolutely true, the smallest red IEC 60309 mains connector will
handle 16 A at 230/400 V, so no big deal for a 3 kW load. However, the
OP seems to have problems with the US market.

>Then you can have smaller filter caps too ;-)

Why do you need filter capacitors after a six-pulse 3-phase rectifier,
if you are going to feed a SMPS anyway. ?

Of course the 6 pulse rectifier has a horrible current waveform, so
some kind o power factor correction might be needed.

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#461672

On Thu, 25 May 2017 17:26:01 +0300,  (upsidedown@downunder.com) said:
> On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
> wrote:
> 
> >We are working on a medical product, which will draw about 3 kW from the 
> >mains.  This is new territory for us, all our previous products were a 
> >few hundred watts max so an off-the-shelf auto-ranging PSU with a 
> >suitable IEC lead was OK for any country in the world.
> 
> Is this peak or average ?
> Is it 3 kW or 3 kVA ? What power factor ?
> 
> >3 kW is OK for a standard outlet in 220V countries, but for North 
> >America, Japan etc we are over the limit for a standard 110V outlet.
> 
> It is not OK for 220-240 V outlets with 10 A fuses. You would have to
> install a dedicated 16 A outlet.
> 
> Any additional loads on the same fuse might eventually blow the fuse,
> a situation which is not appreciated in a hospital environment.
> 
> 
The 3kW figure is peak, for maybe 15 minutes at a time.  Average would 
be closer to a few hundred watts.  Power factor should be close to 
unity, the loads are all either resistive or on the other side of a SMPS 
with active PFC.

My preference, for all the reasons that have come up so far, would be a 
dedicated outlet, but the marketing guys are resisting this as they 
think it creates a potential obstacle to the buyer.  I can't understand 
this myself, we just acquired an environmental chamber which needed its 
own 32A 3 phase outlet.  The cost of installing that was a tiny fraction 
of the unit itself.

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#461681

On a sunny day (Thu, 25 May 2017 16:56:40 +0100) it happened RBlack
<news@rblack01.plus.com> wrote in
<MPG.33910f1241bd21e5989699@reader80.eternal-september.org>:

>On Thu, 25 May 2017 17:26:01 +0300,  (upsidedown@downunder.com) said:
>> On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
>> wrote:
>> 
>> >We are working on a medical product, which will draw about 3 kW from the 
>> >mains.  This is new territory for us, all our previous products were a 
>> >few hundred watts max so an off-the-shelf auto-ranging PSU with a 
>> >suitable IEC lead was OK for any country in the world.
>> 
>> Is this peak or average ?
>> Is it 3 kW or 3 kVA ? What power factor ?
>> 
>> >3 kW is OK for a standard outlet in 220V countries, but for North 
>> >America, Japan etc we are over the limit for a standard 110V outlet.
>> 
>> It is not OK for 220-240 V outlets with 10 A fuses. You would have to
>> install a dedicated 16 A outlet.
>> 
>> Any additional loads on the same fuse might eventually blow the fuse,
>> a situation which is not appreciated in a hospital environment.
>> 
>> 
>The 3kW figure is peak, for maybe 15 minutes at a time.  Average would 
>be closer to a few hundred watts.  Power factor should be close to 
>unity, the loads are all either resistive or on the other side of a SMPS 
>with active PFC.
>
>My preference, for all the reasons that have come up so far, would be a 
>dedicated outlet, but the marketing guys are resisting this as they 
>think it creates a potential obstacle to the buyer.  I can't understand 
>this myself, we just acquired an environmental chamber which needed its 
>own 32A 3 phase outlet.  The cost of installing that was a tiny fraction 
>of the unit itself.

The solution is some Tesla batteries to even the average load...

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#461689

On Thu, 25 May 2017 16:56:40 +0100, RBlack <news@rblack01.plus.com>
wrote:

>On Thu, 25 May 2017 17:26:01 +0300,  (upsidedown@downunder.com) said:
>> On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
>> wrote:
>> 
>> >We are working on a medical product, which will draw about 3 kW from the 
>> >mains.  This is new territory for us, all our previous products were a 
>> >few hundred watts max so an off-the-shelf auto-ranging PSU with a 
>> >suitable IEC lead was OK for any country in the world.
>> 
>> Is this peak or average ?
>> Is it 3 kW or 3 kVA ? What power factor ?
>> 
>> >3 kW is OK for a standard outlet in 220V countries, but for North 
>> >America, Japan etc we are over the limit for a standard 110V outlet.
>> 
>> It is not OK for 220-240 V outlets with 10 A fuses. You would have to
>> install a dedicated 16 A outlet.
>> 
>> Any additional loads on the same fuse might eventually blow the fuse,
>> a situation which is not appreciated in a hospital environment.
>> 
>> 
>The 3kW figure is peak, for maybe 15 minutes at a time.  Average would 
>be closer to a few hundred watts.  Power factor should be close to 
>unity, the loads are all either resistive or on the other side of a SMPS 
>with active PFC.

Taking out from a 10 A 220 V (worst case) outlet for 14 minutes is
stressing the 10 A fuse quite badly. A traditional fuse may survive a
few load cycles, but eventually it will blow. 

I have burnt my fingers several times, when replacing 10 A fuses
loaded with three or four 1000 W lamps on a construction site  :-)
>
>My preference, for all the reasons that have come up so far, would be a 
>dedicated outlet, but the marketing guys are resisting this as they 
>think it creates a potential obstacle to the buyer.  I can't understand 
>this myself, we just acquired an environmental chamber which needed its 
>own 32A 3 phase outlet.  The cost of installing that was a tiny fraction 
>of the unit itself.

Grounding arrangements in old (hospital) buildings can be anything.
You might use some safety related arguments to demand a dedicated and
properly grounded outlet.

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#461693

On Thursday, May 25, 2017 at 8:56:45 AM UTC-7, RBlack wrote:

> > >3 kW is OK for a standard outlet in 220V countries, but for North 
> > >America, Japan etc we are over the limit for a standard 110V outlet.

> My preference, for all the reasons that have come up so far, would be a 
> dedicated outlet, but the marketing guys are resisting this as they 
> think it creates a potential obstacle to the buyer.  I can't understand 
> this myself, we just acquired an environmental chamber which needed its 
> own 32A 3 phase outlet.  The cost of installing that was a tiny fraction 
> of the unit itself.

Some hospital equipment needs backup generator power, or other uninterruptible
power, and the cost of adding 'its own... outlet' may include much infrastructure.

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#462106

On Thu, 25 May 2017 16:56:40 +0100, RBlack <news@rblack01.plus.com>
wrote:


>My preference, for all the reasons that have come up so far, would be a 
>dedicated outlet, but the marketing guys are resisting this as they 
>think it creates a potential obstacle to the buyer.  I can't understand 
>this myself, we just acquired an environmental chamber which needed its 
>own 32A 3 phase outlet.  The cost of installing that was a tiny fraction 
>of the unit itself.

Here's my actual experience.  I moonlighted for several years in the
electro-medical department of the nearby Tri-County hospital.  My
experience was that if the doctors wanted to use a certain gadget that
required special or conditioned power, we were responsible for
providing the outlets in the designated rooms.  The docs call the
shots and not the paper pushers.

I don't think your power requirement would be a serious impediment.

If the unit absolutely has to run on ordinary 120 volt line voltage,
you might consider this architecture.  The device contains a suitable
capacity, high discharge capable lithium battery.  During the "cycle"
or whatever you call it, both the line and the battery supply power.
During the "off" periods, the unit continues to draw full amperage
recharging the battery.

Your sales dweebs would have to decide whether the added cost of the
battery and BMS is worth it vs simply installing the necessary outlet.
The dweebs need to be talking to the department heads and not the bean
counters.

Keep in mind that hospitals are already used to high powered battery
operated devices such as portable X-ray machines, lithotripters and so
on.

John
John DeArmond
http://www.neon-john.com
http://www.tnduction.com 
Tellico Plains, Occupied TN
See website for email address

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#462147

RBlack wrote on 5/25/2017 11:56 AM:
> On Thu, 25 May 2017 17:26:01 +0300,  (upsidedown@downunder.com) said:
>> On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
>> wrote:
>>
>>> We are working on a medical product, which will draw about 3 kW from the
>>> mains.  This is new territory for us, all our previous products were a
>>> few hundred watts max so an off-the-shelf auto-ranging PSU with a
>>> suitable IEC lead was OK for any country in the world.
>>
>> Is this peak or average ?
>> Is it 3 kW or 3 kVA ? What power factor ?
>>
>>> 3 kW is OK for a standard outlet in 220V countries, but for North
>>> America, Japan etc we are over the limit for a standard 110V outlet.
>>
>> It is not OK for 220-240 V outlets with 10 A fuses. You would have to
>> install a dedicated 16 A outlet.
>>
>> Any additional loads on the same fuse might eventually blow the fuse,
>> a situation which is not appreciated in a hospital environment.
>>
>>
> The 3kW figure is peak, for maybe 15 minutes at a time.  Average would
> be closer to a few hundred watts.  Power factor should be close to
> unity, the loads are all either resistive or on the other side of a SMPS
> with active PFC.
>
> My preference, for all the reasons that have come up so far, would be a
> dedicated outlet, but the marketing guys are resisting this as they
> think it creates a potential obstacle to the buyer.  I can't understand
> this myself, we just acquired an environmental chamber which needed its
> own 32A 3 phase outlet.  The cost of installing that was a tiny fraction
> of the unit itself.

There's marketing and there's sales.  I don't know about your product, but 
many expensive devices are sold by "lending" them to the customer with the 
understanding if they like it you will get a PO.  A dedicated power line 
might make this harder to do regardless of who pays for the installation. 
The electrical work would not be expensive in any real sense compared to the 
cost of most medical equipment.  But just the procedural issues involved 
make such a demo much harder to make happen.

The good news in the US is that a 30 amp 208/230/240/2x0 volt (whatever the 
nominal voltage is) is a pretty common standard outlet if you are working at 
that voltage.  Many clothes dryers use them.  The connector is a NEMA 14-30. 
  For higher current devices (like charging cars) the NEMA 14-50 connector 
will supply 50 amps which is way overkill for your device.

The building wiring up to the outlet will need to support the full rated 
current of the connector.  The current capability of your cable can be sized 
to match a fuse in your equipment.  So you don't need to use 10 gauge wires 
in your device cable.  They are big, heavy things.  Does your machine get 
pulled into position?  If so, the bigger the cabling the more of a PITA it is.

-- 

Rick C

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#461696

On Thu, 25 May 2017 17:26:01 +0300, upsidedown wrote:

> It is not OK for 220-240 V outlets with 10 A fuses. You would have to
> install a dedicated 16 A outlet.

Sounds about right. In my part of the world we're on 240V mains, but I do 
believe somewhere else on the planet there's a country that uses over 
400V (single phase) for domestic installations. Anyone know where that 
might be?

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#461703

On Thu, 25 May 2017 17:51:31 -0000 (UTC), Cursitor Doom
<curd@notformail.com> wrote:

>On Thu, 25 May 2017 17:26:01 +0300, upsidedown wrote:
>
>> It is not OK for 220-240 V outlets with 10 A fuses. You would have to
>> install a dedicated 16 A outlet.
>
>Sounds about right. In my part of the world we're on 240V mains, but I do 
>believe somewhere else on the planet there's a country that uses over 
>400V (single phase) for domestic installations. Anyone know where that 
>might be?

While technically it would be possible to have a 400/690 V Wye/Delta
feeds, all the 690 V feeds I have seen are purely delta feeding big
motors.

In Finland, there are several 1000 Vac delta distribution systems
using standard LV hardware (ABC), but it is converted to standard
230/400 V at each village. 

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#461819

upsidedown@downunder.com wrote:
> On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
> wrote:
>
>> We are working on a medical product, which will draw about 3 kW from
>> the mains.  This is new territory for us, all our previous products
>> were a few hundred watts max so an off-the-shelf auto-ranging PSU
>> with a suitable IEC lead was OK for any country in the world.
>
> Is this peak or average ?
> Is it 3 kW or 3 kVA ? What power factor ?
>
>> 3 kW is OK for a standard outlet in 220V countries, but for North
>> America, Japan etc we are over the limit for a standard 110V outlet.
>
> It is not OK for 220-240 V outlets with 10 A fuses. You would have to
> install a dedicated 16 A outlet.
>
> Any additional loads on the same fuse might eventually blow the fuse,
> a situation which is not appreciated in a hospital environment.

When installing a new oven in an old kitchen it's not unusual to install 
a new circuit.  Surely hospitals buying very big expensive equipment can 
have a new circuit installed.

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#461880

On Fri, 26 May 2017 11:55:33 -0400, "Tom Del Rosso"
<fizzbintuesday@that-google-mail-domain.com> wrote:

>upsidedown@downunder.com wrote:
>> On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
>> wrote:
>>
>>> We are working on a medical product, which will draw about 3 kW from
>>> the mains.  This is new territory for us, all our previous products
>>> were a few hundred watts max so an off-the-shelf auto-ranging PSU
>>> with a suitable IEC lead was OK for any country in the world.
>>
>> Is this peak or average ?
>> Is it 3 kW or 3 kVA ? What power factor ?
>>
>>> 3 kW is OK for a standard outlet in 220V countries, but for North
>>> America, Japan etc we are over the limit for a standard 110V outlet.
>>
>> It is not OK for 220-240 V outlets with 10 A fuses. You would have to
>> install a dedicated 16 A outlet.
>>
>> Any additional loads on the same fuse might eventually blow the fuse,
>> a situation which is not appreciated in a hospital environment.
>
>When installing a new oven in an old kitchen it's not unusual to install 
>a new circuit.  Surely hospitals buying very big expensive equipment can 
>have a new circuit installed.

Huh?  In a *very* old kitchen, maybe. In a house that old, likely the
entire house needs to be rewired.

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#461923

krw@notreal.com wrote:
> On Fri, 26 May 2017 11:55:33 -0400, "Tom Del Rosso"
> <fizzbintuesday@that-google-mail-domain.com> wrote:
>
>> upsidedown@downunder.com wrote:
>>> On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
>>> wrote:
>>>
>>>> We are working on a medical product, which will draw about 3 kW
>>>> from the mains.  This is new territory for us, all our previous
>>>> products were a few hundred watts max so an off-the-shelf
>>>> auto-ranging PSU with a suitable IEC lead was OK for any country
>>>> in the world.
>>>
>>> Is this peak or average ?
>>> Is it 3 kW or 3 kVA ? What power factor ?
>>>
>>>> 3 kW is OK for a standard outlet in 220V countries, but for North
>>>> America, Japan etc we are over the limit for a standard 110V
>>>> outlet.
>>>
>>> It is not OK for 220-240 V outlets with 10 A fuses. You would have
>>> to install a dedicated 16 A outlet.
>>>
>>> Any additional loads on the same fuse might eventually blow the
>>> fuse, a situation which is not appreciated in a hospital
>>> environment.
>>
>> When installing a new oven in an old kitchen it's not unusual to
>> install a new circuit.  Surely hospitals buying very big expensive
>> equipment can have a new circuit installed.
>
> Huh?  In a *very* old kitchen, maybe. In a house that old, likely the
> entire house needs to be rewired.

No.  If the house is only a few decades old it probably wouldn't have 
enough in the kitchen for a fridge and a self-cleaning gas oven.

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#461941

On Fri, 26 May 2017 20:32:30 -0400, "Tom Del Rosso"
<fizzbintuesday@that-google-mail-domain.com> wrote:

>krw@notreal.com wrote:
>> On Fri, 26 May 2017 11:55:33 -0400, "Tom Del Rosso"
>> <fizzbintuesday@that-google-mail-domain.com> wrote:
>>
>>> upsidedown@downunder.com wrote:
>>>> On Thu, 25 May 2017 13:05:28 +0100, RBlack <news@rblack01.plus.com>
>>>> wrote:
>>>>
>>>>> We are working on a medical product, which will draw about 3 kW
>>>>> from the mains.  This is new territory for us, all our previous
>>>>> products were a few hundred watts max so an off-the-shelf
>>>>> auto-ranging PSU with a suitable IEC lead was OK for any country
>>>>> in the world.
>>>>
>>>> Is this peak or average ?
>>>> Is it 3 kW or 3 kVA ? What power factor ?
>>>>
>>>>> 3 kW is OK for a standard outlet in 220V countries, but for North
>>>>> America, Japan etc we are over the limit for a standard 110V
>>>>> outlet.
>>>>
>>>> It is not OK for 220-240 V outlets with 10 A fuses. You would have
>>>> to install a dedicated 16 A outlet.
>>>>
>>>> Any additional loads on the same fuse might eventually blow the
>>>> fuse, a situation which is not appreciated in a hospital
>>>> environment.
>>>
>>> When installing a new oven in an old kitchen it's not unusual to
>>> install a new circuit.  Surely hospitals buying very big expensive
>>> equipment can have a new circuit installed.
>>
>> Huh?  In a *very* old kitchen, maybe. In a house that old, likely the
>> entire house needs to be rewired.
>
>No.  If the house is only a few decades old it probably wouldn't have 
>enough in the kitchen for a fridge and a self-cleaning gas oven.
>
Fridges run on 120V.  Self-cleaning *GAS* ovens don't take much
electricity at all (electric ones don't either).  If you're switching
from gas to electricity, sure, but what nut does that?

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