My genny compartment is coming along.

Mex-Busnut · August 23, 2011, 09:09:09 PM

Dear Friends,

We used the front bay behind the driver, which was the former OTR A/C compartment. That is why it already had a huge hole in the floor, and a grate over a large part of the door.

The hole in the floor was filled with a steel grate which I got cheep at a local recycling place. The idea was that the genny weighs over 200 pounds, so it must be strong. Plus I don't want anybody getting under the bay and stealing anything out of there. The grate was welded to the factory steel ribs under the floor.

The idea is to make this bay as heat- and sound-proof as possible, but also well-ventilated. We cleaned out the bay with the acid stuff from my paint-and-body (p&B) shop friend. Then it was primed and painted. Then we layed down the pink insulating panel, and on top of that, 5/8"-inch plywood.

My p&b friend also gave me two 12-volt radiator fans, which I want to use to keep that compartment cool and well-ventilated. I still have notdecided if I will mount one on the door or on the floor. Nor have I figured out if the fan should blow into the compartment, or out.

We installed three small breaker boxes, 2 breakers each:

1. For the camground/external connection.

2. For the 3,000 watt inverter.

3. For the generator.

Only one of these will be on at any given time, of course.

The large panel is the house breakers, and will start with 10 breakers, but can grow up to 20 if needed.

bevans6 · August 24, 2011, 04:15:18 AM

Your fans should blow down out the floor, since if you ever want to run the generator while traveling the natural air flow will be in from the sides and down out the floor. Having a second fan that pushes hot air out the sides may be required if you leave your generator in there and run it while stopped. It will throw off intense heat and rapidly over heat that compartment if you do that.

Using three non-interconnected switches like that for your power supplies can be extremely unsafe. The opportunity to connect two independent supplies together by accident is built right in. For the low cost involved I can't believe you aren't using automatic transfer switches, or at least going the old fail-safe route of have a single cord you just plug into whatever supply you are going to use at the time.

Brian

AndyG · August 24, 2011, 04:56:09 AM

The old AC compartment is an excellent place to put a gererator. I do not think that you will have good luck with those 12V radiator fans. You will need fans which are made for constant duty (100% duty cycle). The radiator fans only run occasionally when installed on a car. If you run them constantly they will burn up in short order. I suggest that you use a good 120V fan or, even better, design your air so that the fan on the engine moves air into and out of the generator compartment. If you use the engine fan you will one less fan to maintain = more relaible.

boxcarOkie · August 24, 2011, 08:07:28 AM

Oooooooooooooooooooooooo, I like that! You are doing a crackerjack job of it there compadre take one-atta boy out of petty cash for a nice, neat, sanitary looking job.

BCO

Len Silva · August 24, 2011, 12:31:25 PM

I would VERY STRONGLY urge you to reconsider that transfer arrangement.

Even though I am quite knowledgeable in things electric, and even if I were the only one to ever go into that locked bay, I am still quite capable of some really dumb $4!t moves. What if it were someone else who thought "I wonder what this switch is for".

The risk potential (not even considering any codes) is very high.

It would be fairly simple to build a one for two interlock between your breaker boxes but a one for three would be a bit of an engineering feat.

If you are looking for the least complicated and inexpensive arrangement, then the cord and plug system wins hands down. You can still keep your three breaker boxes but not use them as a transfer.

wal1809 · August 24, 2011, 01:33:50 PM

The work looks nice! I am glad yall know what yall are talking about because I don't. What is it that is unsafe? I am being sincere btw I really don't know what yall are talking about. I know I joke a lot but not this time. So give it up.

bevans6 · August 24, 2011, 01:47:45 PM

Wal1809, there are three potential sources of power - the extension cable plug into an outside receptacle like a pedestal, the generator, and the inverter. The three small boxes contain switches - the source of power to be in use would be switched on, the others would be switched off. the problem is that there are no interlocks so that only one source of power can be switched on at once. If two independent sources of power are connected, usually things either fry electronics, catch fire, or hopefully blow breakers. The larger issue is improperly back-feeding power to places that it shouldn't go. For example, having the plug on the end of the extension cable live while the generator or inverter is on. A setup like that shown, unless there are subtleties we haven't been made privy to, is completely unsafe and quite illegal anywhere.

The thing is that the equipment to do it right is very readily available and not all that expensive. Automatic transfer switches, of which two will be needed, are around $65 for 30 amp and $125 for 50 amp.

Brian

Mex-Busnut · August 24, 2011, 02:30:30 PM

Thanks for all your input and concern, my friends.

Taking into account your safety concerns, I guess I will go with the plug route until I get North of the Rio Grande and find a place to buy the transfer switches. You would be surprised some of the things that are NOT so "readily available" down here.

Len Silva · August 24, 2011, 02:40:24 PM

Steve,

Since you were planning a manual transfer anyway, moving a plug from one receptacle to another is not much more work than flipping a breaker. Considering where you travel, I would stick with simple, foolproof, and safe.

I would consider moving the three receptacles and the plug up into the bus interior someplace so you don't have to crawl into a bay in bad weather to make the transfer.

Lin · August 24, 2011, 02:51:31 PM

We use the plug arrangement and have in the last bus also. There is one plug for shore and one for generator. The inverter is on a transfer switch set to turn it off when it senses power from either source. Yes, changing the plugs in the bay can be inconvenient, but we have been living with it.

Busted Knuckle · August 24, 2011, 03:37:29 PM

Quote from: AndyG on August 24, 2011, 04:56:09 AM
The old AC compartment is an excellent place to put a gererator. I do not think that you will have good luck with those 12V radiator fans. You will need fans which are made for constant duty (100% duty cycle). The radiator fans only run occasionally when installed on a car. If you run them constantly they will burn up in short order. I suggest that you use a good 120V fan or, even better, design your air so that the fan on the engine moves air into and out of the generator compartment. If you use the engine fan you will one less fan to maintain = more relaible.

Andy,
Good to have your input here on the board! (and we need someone to help us keep your dad inline!)
Sorry I missed you @ your dad's yesterday. Keep an eye on him and don't let him do too much until he gets feeling better!

BK