# 120 volt line voltage isolation/conditioning transformers



## telsa (May 22, 2015)

Lone Crapshooter said:


> I was ask to change out the receptacles in one of the private railroad passenger
> cars that I work on to GFCI's . There are 2 circuits with 8 receptacles on each. The circuits are powered from a line isolation / conditioning transformer . I finished up late and assumed that everything was fine.
> Tonight I find out not all of the loads will work on these circuits. They tell me that the shopvac works fine but the power stapler and the miter saw does not work . When the car was rewired in the mid 80's these circuits were intended do power small loads like table lamps and lap tops the circuit is 2 wire 16 and the circuits are at least 70' long. They seem to think every think worked fine before the receptacles were changed out .
> Undoubtedly I have a voltage drop problem which should not be a problem when the remodel is finished. The GFCI's are only connected only on the line side so there is no interaction between them. One circuit feeds one side of the car the other circuit feeds the other side of the car. Saturday I am going to take 2 meters and use one to check source voltage and the other to check load voltage.
> ...


Electric staplers don't 'talk' with inverter power. Somehow I figure the same logical impasse is happening for you. 

The miter saw is an excessive start up load.


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## RePhase277 (Feb 5, 2008)

What's the transformer rating?


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## Lone Crapshooter (Nov 8, 2008)

At this point in time I do not know. I am going to look at it this Saturday .It's my hobby/ volunteer job.


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## scotch (Oct 17, 2013)

I'm sure you'll find the line conditioner isn't for inductive power feeds...unless it's a very expensive modern one .Maybe batteries and solar power inverters etc...


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## frenchelectrican (Mar 15, 2007)

Lone Crapshooter said:


> I was ask to change out the receptacles in one of the private railroad passenger
> cars that I work on to GFCI's . There are 2 circuits with 8 receptacles on each. The circuits are powered from a line isolation / conditioning transformer . I finished up late and assumed that everything was fine.
> Tonight I find out not all of the loads will work on these circuits. They tell me that the shopvac works fine but the power stapler and the miter saw does not work . When the car was rewired in the mid 80's these circuits were intended do power small loads like table lamps and lap tops the circuit is 2 wire 16 and the circuits are at least 70' long. They seem to think every think worked fine before the receptacles were changed out .
> Undoubtedly I have a voltage drop problem which should not be a problem when the remodel is finished. The GFCI's are only connected only on the line side so there is no interaction between them. One circuit feeds one side of the car the other circuit feeds the other side of the car. Saturday I am going to take 2 meters and use one to check source voltage and the other to check load voltage.
> ...



LC.,, Did you check the line conditioner to see how big the secondary side on Kw size and resvere load capacity to see if handle addtional load. 

what the primary side voltage it was on ? shorepower or locomovite power or HEP ( heat and electric plant ) ?


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## Lone Crapshooter (Nov 8, 2008)

The Head End Power is 480 . I did go down last week and look at both circuits and could not find wrong.
We do not have a wiring diagram for the car and nothing in the electric locker is labeled. There are 5 small transformers 3 of which look to be hooked in a 3 phase bank I am thinking that they power the lights and receptacles . They are stacked on top of each other and I cannot see the name plates on them. The 2 upper most transformers are 32 volt and they supply the reading lights. We are sure of that. There are 3 of the line conditioners one large and 2 smaller it was just a idea of mine that power the receptacles but I cannot be sure. Here again the labels are missing. 
We feel that all the receptacles in questions will ever be used for is lap top and cell phone chargers and they will work fine for that. I did check for voltage drop and only about 1 volt on the farthest receptacle. Knowing how the circuits are wired I can live with that.

LC


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## micromind (Aug 11, 2007)

An electric stapler is pretty close to a bolted fault for about 1/4 of a second. 

The locked-rotor current on a 12 amp universal motor is about 120 - 150 amps at full voltage. 

Most likely, these loads are seen as faults rather than actual loads.


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## Lone Crapshooter (Nov 8, 2008)

I was thinking along the same lines. The stapler was not on the job last weekend and when I checked voltage I was using a variable speed drill running unloaded. I also checked voltage using a power miter saw but when the inrush occurred the voltage sagged only 1 volt.


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