From: Joerg Hansmann (info_at_jhansmann.de)
Date: 2002-01-14 18:50:22
Dear Jim:
----- Original Message -----
From: Jim Meissner <jpmeissner_at_mindspring.com>
To: <buildcheapeeg_at_yahoogroups.com>
Sent: Sunday, January 13, 2002 8:55 PM
Subject: Re: [buildcheapeeg]Patient Safety and Isolation Transformer
...
>You stated that your preference would be "not" to use batteries.
>
>I suggested that we give the customers a choice of using batteries or
>a transformer.
>
>I offered to help you find a "safe" transformer. A medical grade
>transformer is quite expensive.
A medical grade wall wart power supply (e.g. 230 Vac / 8 Vac 200mA)
could be an alternative to batteries or DCDC converters.
But you said, that it is quite expensive...
>My company manufactured transformers for a few years and I know how
>they can fail unless a lot of special care is taken. There are
>"safe" transformers commercially available. If you want me to, I
>can call an old customer and find out the manufacturer and part
>number of a transformer we used in a high meg ohm wheatstone bridge
>circuit. It would work well for this application.
If this transformer is more or less comparable to the above mentioned
specifications I really would like to hear the price.
> Also there are
> filament transformers
Does that mean, there is no ferrite core ?
...
>> I have just emailed traco power products, the manufacturer
>> of the tmv-en DCDC converter series, if their TMV-EN DCDCs are
>> IEC601-1 compliant.
Today I got answer from "traco power products". They have an even better
product than the "TMV-EN" series, called "THI" series:
http://www.tracopower.com/products/thi.pdf
It is fully IEC601-1 appproved:
"...
I/O test voltage: 6000 Vpk
Safety standards and approvals: IEC/EN 60950, IEC/EN 60601-1
rated for 250 VAC (BSI test report)
..."
Regards,
Joerg
This archive was generated by hypermail 2.1.4 : 2002-07-27 12:28:36 BST