The Dog Switch

I bring this up here because I couldn't find any information on it.

Had to bypass the Liberty Watch Dog system to replace a fuel line and power wire to the generator fuel pump. I must have, though I don't remember doing so, flipped on what is labeled the "dog switch" (not the watch dog bypass switch) and that kept the Watch Dog system from allowing the generator to start from any remote switch. Turned the dog switch off and all is well.

This switch is in the first bay on the cabinet with the shore power breakers and the shore power selector switch. It is NOT described or illustrated in the Liberty manual.

The label says something like "Dog switch procedure: To arm, lift toggle switch up, shore power must be plugged in. If generator starts due to shore loss, correct and turn off dog switch and shut off generator."

Which means what ... if this switch is on when shore power is available, the generator will start if shore power is removed?

Maybe I just answered my question?

Jim I think you figured it out. liberty is pretty vague on the watchdog system. They don't publish a wiring diagram. Secret stuff so I hear. On the top center of the panel with the gen start switch there is a group of small wires plugged into a connector above them. This plug when disconnected will disable the generator start, When the Liberty techs saw my Battery disconnect switch going to the gen battery and asked why I told them I did not want the generator to start while in inside storage. They told me to unplug the group of wires previously mentioned that will do the no start and let the gen batt charge while in storage.

Until I saw this dog switch, I thought the only way the generator would start is if the inside auto start switch was on. So I wonder if this dog switch bypasses the auto start and if it is a separate function. I'll talk to Tony in Florida today about it. The other day, he got me inside (!!) the Watch Dog cabinet to check out the circuit board, fuses and switches inside there. I owe him a call back to let him know all is working.

The ribbon cable needs to be unplugged when working on Generator, or turning off your inverters and power to the Coach. As I understand it, the watchdog will not start your generator unless you have pushed the stand-by Gen start button. This will allow the gen to start if your coach batteries drop below 11.8 volts.
If you gen is starting w/o the stand by on, something is wrong with the system. It's probably an extra safety step to un plug watch dog when in storage.

Talked to Troy at Liberty in Florida. This (undocumented on my coach because it was an option) dog switch I'm talking about is not related to the generator starting if the batteries get low. This switch, located in the first port bay on the box with the shore breakers, when armed will start the generator if shore power fails.

All is well and another mysterious Liberty thing explained. Seems like it could be really useful in some situations. I wonder if other converters do something like that.

Jim

Any way that you could post a picture of the "Dog" switch that you mentioned?

I'm just wondering if it's the same as mine. Seems like a nice option to have.

Thanks,

Paul

Quote:

---

Originally Posted by phorner

Any way that you could post a picture of the "Dog" switch that you mentioned?

---

Paul, here's a link to a picture http://2000liberty.info/P8154211.JPG

I guess I haven't been paying attention ... just saw you have coach #434. Ours must be sisters!

I was told anytime you flip that safety protected by pass switch for the Watch Dog you had to disconnect the ribbon cable.

Mike

Mike, that makes sense. You are talking about the switch in that picture? Or are you talking about the bypass switch on the box below the Watch Dog system in the second bay?

I haven't tested the operation of the switch in the first bay to see how and when it actually works and how it works with other systems. I do know that without shore power and with this switch on, the remote generator start switches do not work.

Jim,

Thanks for the photo. I'll bet our two buses were certainly in Chicago at the same time! However, no "Dog switch" on ours.....

Kind of related to this thread is the auto-start feature of the Liberty Watch Dog system.

When placed in the auto-start position, at what battery voltage does the generator start? And, will it automatically shut down the generator when the battery voltage reaches a pre-determined value? Are any of these values adjustable?

I've had our generator start automatically, but then shut it down manually after the batteries had charged for a while and we were ready to get under way.

Others can be more precise, but I've found that the generator starts when the batteries drop below 11 volts. Don't know the exact figure and wouldn't imagine that it's adjustable. When the batteries are getting low, and we apply some additional load, like the coffee maker, for example, I'll see the generator running lights go on and off for several minutes, perhaps until the load drops, and then it settles back into watching. Soon thereafter the generator will start when it really needs to. I've never seen it shut down when the batteries are charged, though. I don't think it does.