Generator Help Needed

[seanmcgillivray]

I have a 695A. Serial number 96029.

I am having trouble getting the right generator online. The problem has been intermittent and has even switched sides. For example todays test flight saw the left out (intermittent as it was offline, online for taxi and offline during the roll).

Shut down after landing and the left comes online and the right side is dead. After switching GCUs and Gens the problem still stayed on the right side.

Any thoughts would be greatly appreciated!

Sean

[donv]

Sounds like a paralleling problem? If you turn the left one off, does the right one come online?

[seanmcgillivray]

Negative.

Everything checks out. Grounds, field wire, switches, contractors. Only I haven’t done is switched the SRLs.

[donv]

When both are on line, what do the ammeters show? Is the load balanced? And is the voltage from each about the same?

[seanmcgillivray]

Individually traced and checked every connection and wire in the system. Had a reset switch that seemed troublesome and got it traced down to a GCU.

Just bought a overhaul unit outright and will send the bad one in for overhaul. Plan on having a spare on the shelf.

[Mark S]

I had a similar issue that was easier to trace to a GCU.
I always wondered what spares would be the most useful to have around, or carry in back. I hear Starter-Gens are popular. GCU’s make sense.
I was advised to have a spare speed switch handy. Still don’t have one though.

The odds of needing and using the spare is inversely proportional to the cost to acquire.

[seanmcgillivray]

Saga continues. Popped in the new GCU and it was DOA out of the box. Overhauled unit tagged 12/21.

Have that going back and a replacement for 10 AM delivery today. Will keep you posted.