MEP-805B no hrz/power readings

[Billy2642]

That is what the "field flash" feature does as part of the unit starting up. When you hold the main switch in the "start" position that flashes the field to magnetize the alternator.

If you have a unit that makes power when starting but doesn't make power when you release the start switch its the field flash circuit that is causing the unit to make power while starting.

What you are describing would only be necessary for a self excited alternator like what you buy from your big box home store. These aint those (I'm southern).

welp,!scratch that idea then. I have 3 generators that I'm having issues with. First is the one I started this thread about: 2001 MEP-805b that isn't producing any herts or voltage, then I have a MEP-806a that is producing 60 hertz but only about 55 volts and then I have a 1995 MEP-805a that will only produce 54 hertz and 50 volts.

 

[DieselAddict]

How far have you gotten in troubleshooting in the manual?

 

[Billy2642]

How far have you gotten in troubleshooting in the manual?

my knowledge for electricity is limited and I'm learning as I go. For troubleshooting, I've tried cleaning all related connections, cleaned out the fuel systems, checked and swapped relays behind the panels, and stuff like that. I took the 2001 MEP-805b that isn't producing anything to city generator shop and best they could come up with is the voltage regulator. They didn't seem real sure though and I'd hate to spend 5-600 on a voltage regulator to just have nothing fixed.

 

[DieselAddict]

Here is a place to start.

Download the -24 manual for the 805 and go to page 148. That is the sheet describing the connections on the diagnostic port. If the equipment will run but not make voltage you'll want to check the DC exciter field voltage (pin "F"). See what you have there. You can go down the list and compare what you see on different pins with the expected output column. Be sure to check the notes so you know what mode the generator needs to be in to take the reading.

Edit:

Then go to page 218 of the -24 manual and see if you can follow the troubleshooting instructions starting with section 11.

Testing voltage regulator is on page 241.

 

[Billy2642]

Here is a place to start.

Download the -24 manual for the 805 and go to page 148. That is the sheet describing the connections on the diagnostic port. If the equipment will run but not make voltage you'll want to check the DC exciter field voltage (pin "F"). See what you have there. You can go down the list and compare what you see on different pins with the expected output column. Be sure to check the notes so you know what mode the generator needs to be in to take the reading.

Edit:

Then go to page 218 of the -24 manual and see if you can follow the troubleshooting instructions starting with section 11.

Testing voltage regulator is on page 241.

what year -24 TM are you using? I have the OCT 96 PDF of the Tam and the pages you mention aren't what they should be

 

[DieselAddict]

Download the manuals from the technical section here. Those are the ones I just looked through to give you page numbers.

 

[Billy2642]

Download the manuals from the technical section here. Those are the ones I just looked through to give you page numbers.

great news! I got the 805a running and registering the correct hertz and bolts. I ended up swapping out the magnetic pickup and adjusting and readjusting it until I got between 2 and 3 vac on wires 16 and 17 on the governor control board. Did that and I could immediately tell when I started it up that it was running a little higher rpm. I then excited the system and boom, WE HAVE POWER! Now if only I can get the 806a and 805b going next

 

[DieselAddict]

Excellent. Keep it up!