MEP-003 Frequency meter issue

[Corvette1974]

Hello.

Ok So I still have to post the first start up video of my MEP-003. It runs like a demon. I almost have it ready to power the house, just need the transfer switch, but it's all wired.

The problem I'm having is with the frequency gauge. Now I know I should check the TM's but I figure it may just be a common transducer problem or somthing like that.

Basically start it up. Frequency barely changes (just like normal warm up governor frequency changes). After a while the gauge just starts to read like between 55 HZ and 60HZ like in the middle between them (when the actual freq. is 60). It worked fine up until then, actually reading correctly. Now whereas the gauge is wrong, I follow my Fluke MM and it tells me the freq. is a perfect 60.00. So i dont need the gauge, as I'd use the MM anyway to fine tune it, but I'd like to fix a blatant "problem" with the gen.

You guys got any ideas?

Thanks,
Will

 

[Corvette1974]

Ok so I did some more research and found some good stuff. I think when I go home this weekend I'll just take the gauge and transducer out and take the transducer apart and replace all the soft components. Where is the transducer located? Main control box or in the side electrical box?

Will

 

[steelandcanvas]

http://www.steelsoldiers.com/generator-electrical-tms/77624-tms-generators.html

 

[Triple Jim]

Specifically, page 4-41 of manual TM5-6115-585-12.pdf

 

[Corvette1974]

Thanks- I know where it is now. But i couldnt find anything on diagnosing it. I'll check it out more this weekend.

Will

 

[GREENMV]

Thanks- I know where it is now. But i couldnt find anything on diagnosing it. I'll check it out more this weekend.

Will

OK, I am feeling like my left foot Is nailed to the floor. I have searched, searched, and done some more searching on how to bench test the MEP-002 & 3 frequency gauge & transducer. Can some one guide me In the right direction to find this info or does someone have a step by step guide on how to do this? Any help is appreciated. Thanks

 

[PeterD]

Well I test and calibrate with a standard power outlet. The transducer takes 120 volts in, and our power in the US is very accurate. Now if you have to calibrate for both 50 and 60 hz, then you need a low frequency signal generator and a step-up transformer (and perhaps an amplifier) to calibrate at both frequencies.

 

[GREENMV]

A transducer is a device that converts a signal in one form of energy into another form of energy. "WIKI" I know the transducer input Is 120V. what am I supposed to get on the output side for the test purpose. And I figure once I know that, I can also test the HZ gauge by supplying the gauge with that Input to test the gauge separately. I know there a lot of people here that have a lot more smarts than my novice attempts. Help

 

[PeterD]

... I can also test the HZ gauge by supplying the gauge with that Input to test the gauge separately. I know there a lot of people here that have a lot more smarts than my novice attempts. Help

Well, here's my take on it:

1. The meter/transducer are a matched pair meant to be used together. No point in individual testing, but...

2. Look on the meter and it will be marked with the full scale (FS) current rating. Maybe (going by memory here, so I could be off) 200 uA or 500 uA? Find that value (usually lower right of the face) and with another (known accurate) meter in series apply current sufficient to make the accurate meter read the full scale reading on the test meter. The movement is (AFAIK) linear so you can interpolate all readings from zero to full scale.

3. Again, as the transducer matches the meter, it's maximum output would be about the FS reading of the meter, and the 60 hz reading would be easy to compute.

But why bother? Do a simple set of tests on the meter then calibrate as a pair the way the manufacturer does. (Simple tests might include testing FS reading, and testing to ensure the needle moves freely and properly at all significant points.)

BTW, just a caution: it is very easy to destroy a meter with too much current! Be very careful, always start at zero current and slowly increase current when testing meters so as to not exceed the FS value. Exceeding FS values can bend pointers, damage the coil(s), break the internal parts, etc., all of which create an expensive paper weight!