For DIY projects, I bought a medical grade isolation transformer from eBay. The traf is made by Toroid. Not sure if Toroid is in business. They don't answer phones and don't reply to e-mails. Some of their pages on their web-site are not working.
Can anyone tell me what type of AC plug is required for the 4 AC receptacles fitted in the front panel?
Standard AC power cord with circular ground pin obviously doesn't fit. I assume the hospital equipment has different plugs than equipment designed for home use. The neutral and the hot conductor pins (unlike the std AC cord) has sockets of different shape and size. The front label states neutral conductor is not grounded hence the isolation from the Ground at the utility pane which is great but why disallow the use of standard AC power cord? I can use this traf with an improvised cord but not being able to use standard AC power cord is inconvenient. I'm thinking of changing the receptacles or find a place which sells suitable power cord. Thank you for your comments in advance.
Can anyone tell me what type of AC plug is required for the 4 AC receptacles fitted in the front panel?
Standard AC power cord with circular ground pin obviously doesn't fit. I assume the hospital equipment has different plugs than equipment designed for home use. The neutral and the hot conductor pins (unlike the std AC cord) has sockets of different shape and size. The front label states neutral conductor is not grounded hence the isolation from the Ground at the utility pane which is great but why disallow the use of standard AC power cord? I can use this traf with an improvised cord but not being able to use standard AC power cord is inconvenient. I'm thinking of changing the receptacles or find a place which sells suitable power cord. Thank you for your comments in advance.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
They are unusual for a reason, they are power output. Having live exposed terminals is a bad idea.
The OP wants a IEC female - IEC male lead, they are commonly used for power distribution from UPS (uninterrupted power supply). An alternative is something like this http://www.ebay.com.au/itm/15cm-UPS...ires_Cables&hash=item20cb701e77#ht_1254wt_954
The OP wants a IEC female - IEC male lead, they are commonly used for power distribution from UPS (uninterrupted power supply). An alternative is something like this http://www.ebay.com.au/itm/15cm-UPS...ires_Cables&hash=item20cb701e77#ht_1254wt_954
They are unusual for a reason, they are power output.
Having live exposed terminals is a bad idea.
Hi,
You are quite right, and that makes perfect sense.
The lead and input socket I showed are exactly that,
mains input, whilst here its mains output, so your
going to need a unusual mains lead, male to female.
rgds, sreten.
My advice to change them is dreadful .... muppet ....
Did a little more research to find out the receptacles are IEC 60320-2-2 Class I Power Components - plug connector Sheet E to be exact.
Just one Sheet E connector is $13 plus S&H for one plug at Amazon !
http://www.amazon.com/Conntek-60905-Bare-Connector-Sheet/dp/B001H4J3M4/ref=pd_bxgy_lg_img_y
I'm definitely inclined to change the Sheet F outlets to standard female outlets since they are power output. A cheaper alternative is AC Female Outlet~PC Male Power Adapter Cable/Cord/Wire IEC320 C13/C14.
No wonder the transformer was priced rather low on eBay. I overlooked the fact that outlets will not work with standard AC connector plugs. Fortunately it came with it's own power chord, standard 3-prong plug. Aside from the receptacle issue, it's appears to be well-made, included documentation showing the circuit.
Thank you for your comments.
An externally hosted image should be here but it was not working when we last tested it.
Just one Sheet E connector is $13 plus S&H for one plug at Amazon !
http://www.amazon.com/Conntek-60905-Bare-Connector-Sheet/dp/B001H4J3M4/ref=pd_bxgy_lg_img_y
I'm definitely inclined to change the Sheet F outlets to standard female outlets since they are power output. A cheaper alternative is AC Female Outlet~PC Male Power Adapter Cable/Cord/Wire IEC320 C13/C14.
No wonder the transformer was priced rather low on eBay. I overlooked the fact that outlets will not work with standard AC connector plugs. Fortunately it came with it's own power chord, standard 3-prong plug. Aside from the receptacle issue, it's appears to be well-made, included documentation showing the circuit.
Thank you for your comments.
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DO NOT change the outlet connectors on the device. This will have exposed live parts and be a SERIOUS health hazard.
DO purchase the correct leads - IEC 320 Sheet E to IEC C13 Power Cord or the IEC -> 3 pin plug adapter for your country (Aus equivalent linked in my previous post).
DO purchase the correct leads - IEC 320 Sheet E to IEC C13 Power Cord or the IEC -> 3 pin plug adapter for your country (Aus equivalent linked in my previous post).
I use a couple of these transformers in my system, the proper plugs are readily available on eBay for short money as are short pigtails with standard NEMA 15A sockets on one end and IEC with male pins on the other.
No need to modify the transformer, and in fact since all of the components in my system use IEC connectors I am contemplating changing the plugs on the power cables to use the IEC with male pins.
I've got a 600VA and a 1kVA made by Toroid Corp of Maryland, the maker of your unit. The company is very much still in business, in fact we have a bunch of these at work. (I work in medical electronics.)
Note that the output is floating and interestingly I found that the overall hum level in my system decreased very slightly.
No need to modify the transformer, and in fact since all of the components in my system use IEC connectors I am contemplating changing the plugs on the power cables to use the IEC with male pins.
I've got a 600VA and a 1kVA made by Toroid Corp of Maryland, the maker of your unit. The company is very much still in business, in fact we have a bunch of these at work. (I work in medical electronics.)
Note that the output is floating and interestingly I found that the overall hum level in my system decreased very slightly.
Sourcing that cable connector should be pretty easy at a computer recycler. It used to be common for the computer CRT monitor to be plugged into the back of the computer PS. I had at least 1 old PC monitor and 1 old Mac monitor that that had the male IEC connector for power.
Plenty of suitable cords available at Digikey, Mouser, etc. A typical example:
AK500-OE-11-1-R Assmann WSW Components | AE9911-ND | DigiKey
Dave.
AK500-OE-11-1-R Assmann WSW Components | AE9911-ND | DigiKey
Dave.
Those IEC power input/output sockets are perfectly normal and standard in Europe. The cables are widely available over here.
We're not exactly an IEC backwater over here either..
They're quite readily available from most electronic component suppliers, and at hamfests.
I understand an iso traf connects two separate transformers magnetically. In this particular Toroid traf, the isolated side's neutral is not grounded. Let's assume by mistake it was. For the example of a 2-prong classic radio, plugged into the Toroid iso-traf, what is the risk for a DIY'er who has taken precations of not grounding himself?
'connects two windings magnetically' not 'two transfomers'
If the output from an isolation transformer is grounded on one side then connected to an AC/DC radio then you have largely undone the benefit of isolation unless you can guarantee that you have grounded the 'chassis' side. The only benefit you get is a higher impedance supply so possibly a bit less 'shock' current.
If the output from an isolation transformer is grounded on one side then connected to an AC/DC radio then you have largely undone the benefit of isolation unless you can guarantee that you have grounded the 'chassis' side. The only benefit you get is a higher impedance supply so possibly a bit less 'shock' current.
Toroid iso-traf upgrade
Thanks... when I read this I gathered the courage to violate Naim's rules - i.e., not to plug a Naim unit into any noise supression unit.
I plugged my integrated amp (Naim Nait-1) into the Toroid iso-traf, the noise drop was significant. There was more music and information - I had to turn it louder. Naim's line-stages have too much noise. Nait-1 is 80's technology but one shoe-size box can surprise you. When it came out it sold for $400-500 but now you're lucky if you can get one on eBay for less than $800. Naim will emphasize selling their customers expensive external PSU upgrades - clever marketing that have made them millions.
The difference I heard with the Toroid iso-traf (much cheaper than a Naim PSU) was at least as good as adding an external Naim PSU which sells used/new between $700-1500. Nait-1 is not upgradable by a separate Naim PSU but more modern Naim pre-amps and cd players are. With Nait-1, it's possible to upgrade the internal monolithic power regulation circuit with a super-regulator. Naim recommends against noise-supression, filters, etc claiming it will degrade or change the sound. Well with Toroid iso-traf plugged in, Naim's unmistakable PRAT is still there and grooving better than ever. To my ears it sounds as good if not better as adding one of their Hi-Caps (external PSU) - maybe it's the psycho-acoustic effect of paying less and getting something in return .
I've got a 600VA and a 1kVA made by Toroid Corp of Maryland, the maker of your unit. The company is very much still in business, in fact we have a bunch of these at work. (I work in medical electronics.) Note that the output is floating and interestingly I found that the overall hum level in my system decreased very slightly.
Thanks... when I read this I gathered the courage to violate Naim's rules - i.e., not to plug a Naim unit into any noise supression unit.
I plugged my integrated amp (Naim Nait-1) into the Toroid iso-traf, the noise drop was significant. There was more music and information - I had to turn it louder. Naim's line-stages have too much noise. Nait-1 is 80's technology but one shoe-size box can surprise you. When it came out it sold for $400-500 but now you're lucky if you can get one on eBay for less than $800. Naim will emphasize selling their customers expensive external PSU upgrades - clever marketing that have made them millions.
The difference I heard with the Toroid iso-traf (much cheaper than a Naim PSU) was at least as good as adding an external Naim PSU which sells used/new between $700-1500. Nait-1 is not upgradable by a separate Naim PSU but more modern Naim pre-amps and cd players are. With Nait-1, it's possible to upgrade the internal monolithic power regulation circuit with a super-regulator. Naim recommends against noise-supression, filters, etc claiming it will degrade or change the sound. Well with Toroid iso-traf plugged in, Naim's unmistakable PRAT is still there and grooving better than ever. To my ears it sounds as good if not better as adding one of their Hi-Caps (external PSU) - maybe it's the psycho-acoustic effect of paying less and getting something in return .
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