MEP-002A Low / High Hz frequency question

[underp2]

I checked the frequency gauge - 56 Hz. Read some searched threads, and decided I didn't trust the gauge. Tried using my Fluke 187 meter, and got unsteady frequencies from 40-400. Tested my meter in household socket - 60. Decided I didn't trust my meter. Borrowed one from work and found the frequency to be ~48 Hz. Increased RPM and got it to 60 Hz on the digital meter. The gauge still reads 56. I also found that I get the most vibration at 60 Hz. Most of the vibration comes from the trailer canopy ribs vibrating and from the metal panels on the generator vibrating. This thing purrs steady & quiet at 64 Hz.

Would running it @ 64 Hz hurt anything?
Did running it @ 48 Hz hurt anything?

Thanks,

Pete (1st post)

 

[dependable]

60 Hz is std for USA alt current. Running at 48 or 64 Hz probably won't hurt genset, but you increase the chances of damaging your appliances the more you deviate from the 60 Hz. I am no expert, but your question may reflect a incomplete understanding of what you have. Please check out TMs and understand basic operating and safety procedures .

 

[Keith_J]

Running an 002/003A at frequency lower than 55 Hz can overload the output transistor on the voltage regulator.

Frequency is set by engine RPM. It is impossible to get 400 Hz from a 002A unless you were to replace the field with a 20 pole unit and run it at 2400 RPM. It has a 4 pole field which causes two field reversals per revolution...1800 RPM / 60 seconds per minute is 30 revolutions per second. Two field reversals per second gives 60 cycles per second.

 

[underp2]

Running an 002/003A at frequency lower than 55 Hz can overload the output transistor on the voltage regulator.

Frequency is set by engine RPM. It is impossible to get 400 Hz from a 002A unless you were to replace the field with a 20 pole unit and run it at 2400 RPM. It has a 4 pole field which causes two field reversals per revolution...1800 RPM / 60 seconds per minute is 30 revolutions per second. Two field reversals per second gives 60 cycles per second.

I think the 400 Hz was somehting wrong with the meter, Dave's meter worked fine. It surprised me that mine read 60 Hz in the workshop receptacle, then fluctuated wildly when reading the generator.
I don't have 20 poles, so it must be the meter

 

[Keith_J]

Only the 10 kW came in a 400 Hz version which have a 20 pole field.

If you are loading the generator with a motor, especially a universal motor (drill, saw etc), the low power factor can cause a digital frequency meter to go batty.

Since you are new here, be very careful with using the convenience outlet on the front panel. It is powered by one stator winding (out of six) so it won't support loads greater than 500 watts. And that is stretching it because it can cause over-voltage in the five non-loaded windings.

 

[jbk]

check your valves adjust as per tm. 010 in. intake and .007 exh. they vibrate pretty bad when their out. running your hrts, to high or to low might put stress on the a/c regulator.

 

[Isaac-1]

Often an unsteady digital frequency meter will clear up when you add a simple resistive load to the output, such as a 100 watt light bulb or a small heater. I am somewhat surprised you had problems with the Fluke 187 though, usually it is the cheaper meters with the problem, my 87V works great on every generator I have checked with it.

Ike

p.s. many mechanically governed small generators are set around 62-63 hz no load to allow for a drop to 58 hz at full load.

 

[PeterD]

Virtually all appliances will work in the 50 to 60 Hz range without problems. Only a very few are sensitive to frequency. However, things like built-in clocks etc, will be inaccurate whenever the frequency deviates from the 60 Hz standard. (But OTOH, no clock should be trusted when being powered by a backup generator!)

I doubt you damaged anything at those readings, were you to have damaged something you'd know it already.

 

[Keith_J]

Proper connection of an external frequency meter is essential for proper reading. A loose connection can cause false readings. There is not much current as the meters are very high impedance.

 

[underp2]

Virtually all appliances will work in the 50 to 60 Hz range without problems. Only a very few are sensitive to frequency. However, things like built-in clocks etc, will be inaccurate whenever the frequency deviates from the 60 Hz standard. (But OTOH, no clock should be trusted when being powered by a backup generator!)

I doubt you damaged anything at those readings, were you to have damaged something you'd know it already.

So does that mean that I will be fine to run it @ 64 Hz? This smoothed out nearly all of the vibration.

I will br running regular household stuff (fridge, freezers, furnace, well pump, lights, coffe maker, microwave). Is a MEP-002a capable of running a clothes dryer? if most of the other stuff is turned off? Maybe that is a good way to perform load testing...

Otherwise, I was planning on hooking it up to the workshop. I can run the stock tank heaters for monthly 'exercise'. At 1500 watts each, they can create a good, steady load.

Anyone have a good way of repairing the latches for the ASK? the clamps are worn. This makes them clamp loosely, which allows them to rattle a lot. That probably creates more wear.

After I tighten up the clamps, I'll use some gasketting material to help the access hatches close tightly.

 

[underp2]

Often an unsteady digital frequency meter will clear up when you add a simple resistive load to the output, such as a 100 watt light bulb or a small heater. I am somewhat surprised you had problems with the Fluke 187 though, usually it is the cheaper meters with the problem, my 87V works great on every generator I have checked with it.

Ike

p.s. many mechanically governed small generators are set around 62-63 hz no load to allow for a drop to 58 hz at full load.

That answered my question. Thanks, Ike.

Pete.