Pirotess
Member
- 18
- 37
- 13
- Location
- Lavaca County, TX, USA
Another update and more questions...
Well, I got an oil gauge mod installed. It showed 42psi at startup, and it dipped to 34psi after warming up under light load (about 12A L1/12A L3). It is nice to be able to look at the analog oil for confirmation. The panel seems to be around the same pressures.
The Frequency Transducer seems to check out OK as well, and the gauge shows the correct 60Hz!
Well, now for the bad news. I was trying to put some load on it, I think I was up to about the same 35ish Amps, when the PRC Ammeter suddenly shot up and the over load safety light tripped. The load was nowhere near enough to actually do that though...
And now my test loads show up around double on the PRC than what they did before..?
I have been pouring over the diagrams, and have one culprit so far:
R10, R11, & R12 should be 7.5 Ohms, but are reading around 1 Ohm each. They have gone bad.
R13-R15 check good.
So, I can't seem to find any replacements for them ( HLM-20-10Z7R50J ). Nowhere to be found online!
I am looking at getting some CAL-RMCX250 20W 1% 7.5 OHM Power Resistors, but I will have to modify the mounts if I do. The specs look the same though, so I think they will work. Does anyone know anywhere to get the originals?
Second, has anyone had this problem before? Is it just bad resistors, or do I need to look for something else that is bad? The way I understand it, the circuit is connected to S8, S6, K8, CT1-3, and R10-12. Do I need to check something on K8 (the Overload Relay)? What would have caused this?
Thank you for the help!
Well, I got an oil gauge mod installed. It showed 42psi at startup, and it dipped to 34psi after warming up under light load (about 12A L1/12A L3). It is nice to be able to look at the analog oil for confirmation. The panel seems to be around the same pressures.
The Frequency Transducer seems to check out OK as well, and the gauge shows the correct 60Hz!
Well, now for the bad news. I was trying to put some load on it, I think I was up to about the same 35ish Amps, when the PRC Ammeter suddenly shot up and the over load safety light tripped. The load was nowhere near enough to actually do that though...
And now my test loads show up around double on the PRC than what they did before..?
I have been pouring over the diagrams, and have one culprit so far:
R10, R11, & R12 should be 7.5 Ohms, but are reading around 1 Ohm each. They have gone bad.
R13-R15 check good.
So, I can't seem to find any replacements for them ( HLM-20-10Z7R50J ). Nowhere to be found online!
I am looking at getting some CAL-RMCX250 20W 1% 7.5 OHM Power Resistors, but I will have to modify the mounts if I do. The specs look the same though, so I think they will work. Does anyone know anywhere to get the originals?
Second, has anyone had this problem before? Is it just bad resistors, or do I need to look for something else that is bad? The way I understand it, the circuit is connected to S8, S6, K8, CT1-3, and R10-12. Do I need to check something on K8 (the Overload Relay)? What would have caused this?
Thank you for the help!