Level-Up hydraulic jacks - trouble retracting 1 of the jacks - cold weather

[steve&renee]

Follow the heavy red wire connected to the trombetta solenoid. That should lead you to the breaker for the hydraulic pump motor. It should be an autoreset breaker. On my previous trailer with the hydraulic system, I replaced what was a 50 amp breaker with an 80 amp manual reset breaker. No more annoying break/reset cycles. Current draw was measured as high as 67 amps during system operation.
The hose(s) to that leg may be pinched causing higher pressure demand when colder oil is being pumped.

It's been so cold until March hit that I couldn't get motivated to keep trouble-shooting the jack failing to retract. But I did order an 80 amp breaker that I planned to install "proactively." Well in March, the temps climbed back into the 30's and 40's again, so I went to the trailer and began working on wiring the hydraulic pump with the 80 amp breaker. Still standing in snow, but at least I didn't need a heavy coat and gloves. You won't believe what I found.

When my trailer was new, I had that problem where the slides wouldn't retract because the original wiring for the pump was protected by just a 50 amp breaker. I took the unit to the dealer and they "fixed" it under warranty and based on a solution recommended by GD. The GD "fix" for the undersized 50 amp breaker was to add a second 50 amp breaker and jumper them together. Like this:




Based on my web searches, this is terribly wrong. It works *only* if the the resistance thru each breaker is identical, which won't be the case as the breaker degrades over time and if the breakers' electrical connections aren't perfect. Can't believe GD employs electrical engineers that recommended this approach. My understanding is it's a Code violation:

"Paralleling as described is in violation of the National Electrical Code, article 240.8:

Fuses or Circuit Breakers in Parallel. Fuses and circuit breakers shall be permitted to be connected in parallel where they are factory assembled in parallel and listed as a unit. Individual fuses, circuit breakers, or combinations thereof shall not otherwise be connected in parallel.

"
Also can't believe I left the dealer without knowing exactly what they did. I've learned since that I'm the one who's responsible for *everything* on my trailer.

So I got rid of the GD "fixed" configuration and installed my new 80 amp breaker between the pump and battery plus.

It's all working at 40+ degrees. I'll see if *my* fix did the trick when it drops down to the 20's again. (That should be guaranteed. It's Minnesota don't ya know.)

-Steve

[Jlawles2]

So I have ran into return line issues like you are mentioning. If there is a pressure sensor in the system that is measuring the input hydraulic pressure and the pressure maxes out (signifying either overload or roll retract) the system shuts itself down.

Also with Lithium batteries (i only run 3.5Ah batteries in RC stuff, the static voltage and the running voltage can be extremely different. Your system may be seeing voltage "sag" that drops it another 1v or more during load.

[TedS]

It's all working at 40+ degrees. I'll see if *my* fix did the trick when it drops down to the 20's again. (That should be guaranteed. It's Minnesota don't ya know.)

I never did like the solution of parallel breakers. The 80 amp breaker( 80 amp breaker lippert0058.pdf )will solve the problem.
The hydraulic fluid is ATF, it should flow at 20F.

[steve&renee]

I never did like the solution of parallel breakers. The 80 amp breaker( 80 amp breaker lippert0058.pdf )will solve the problem.
The hydraulic fluid is ATF, it should flow at 20F.

Temp dropped down to mid-twenties last night, so I went over to the trailer to test the cold weather operation of the jacks after having rewired the parallel 50 amp breakers with a single 80 amp breaker. Works like a champ! Problem solved!

Thank you, Ted, for figuring out my problem. Hat's off to you and all the great people on this forum.

-Steve

[TedS]

Thanks for the feedback. Glad you have resolution.