# Mtm-120



## CYoung (Apr 19, 2013)

> I measured from the + to ground and still had no current. I went right to the MTM output terminals and was getting 0 there too..


You would put your meter in series in order to measure mA.


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## glen1971 (Oct 10, 2012)

CYoung said:


> You would put your meter in series in order to measure mA.


I was in series to the PLC input (+ in from MTM and + out to PLC).. Series from the "+" on the MTM to gnd at the PLC (Checks for a bad point on the card).. Series at the MTM with the + to the PLC (Broken wire?).. Series between the + and - at the MTM, with the PLC wires unhooked (Broken wire??)... 

Shields are grounded at the MTM only...


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## CYoung (Apr 19, 2013)

Sorry, I misunderstood how you were measuring. Without being there, I would say that if you are measuring, 0 mA on the output of the MTM (terminal 58 and 59) I would probably say that the MTM is bad. Here is a link I found that relates to the MTM you referenced:

http://www.gedigitalenergy.com/products/manuals/269p/269pman-e4.pdf

I skimmed thru it real quick, it appears that the 4-20 out can be set for different things. Maybe someone was playing around and messed up a setting....


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## glen1971 (Oct 10, 2012)

Thanx.. I'll give it a read today!


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## glen1971 (Oct 10, 2012)

CYoung said:


> Sorry, I misunderstood how you were measuring. Without being there, I would say that if you are measuring, 0 mA on the output of the MTM (terminal 58 and 59) I would probably say that the MTM is bad. Here is a link I found that relates to the MTM you referenced:
> 
> http://www.gedigitalenergy.com/products/manuals/269p/269pman-e4.pdf
> 
> I skimmed thru it real quick, it appears that the 4-20 out can be set for different things. Maybe someone was playing around and messed up a setting....


Thanx.. the manual was for the 269 Multilin, and terminals 58/59 aren't used. The MTM is hooked to Term 84 and 85 and is on RS-485 and provides 3 analog outputs to the PLC..

https://www.google.ca/#q=multilin+mtm-120+manual


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## JRaef (Mar 23, 2009)

The persistent low voltage to the PT inputs likely also meant it was fluttering on and off at some point and over heated an A/D converter inside, which may have damaged everything else connected to the DC side. You could tear it apart and look for cooked parts on the PC boards, but I wouldn't bother. It's likely not repairable anyway or would cost too much to fix.


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## glen1971 (Oct 10, 2012)

Thanx for the reply JRaef... 
I talked to the client yesterday and since this is the last 269 they have in use in this area, they are most likely going to upgrade to a 369 and use it's outputs to the PLC, depending on recommendations from their Medium voltage service folks..


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