Onan DJCL remote start?

[DieselCJ]

We have a Onan DJCL 12KW diesel air cooled generator mounted on a concrete slab on the side of the house (installed new in 1993).

When the power goes out we go outside, open the housing (wood) door and start it. I was thinking about piggybacking the switches and running longer wires to the starter and glow-plug switches so it can be started from inside the house.

The starter switch looks like a simple momentary on-off-on switch I can get at an electrical supply store, but the glow plug switch has three leads, though it is a momentary in one direction. These wires will only have to be about 15’ to get inside the house.

Going to an extreme…
Can a transfer switch like this http://www.coloradostandby.com/catal.../products_id/1 be used with the generator I have, or is there something special used with diesels? At the time when we got the generator, automating it would have cost about $5,000 (according to the installer).

Thanks,
John

[Steve Dawkins]

John,

I don't know what the "L" stands for in the model number, but DJC's are typically 4 cylinder air cooled units. Yours may have the capability of connecting remote start/stop/preheat switches without having to piggyback wiring on the switches in the control box of the genset. Remove the control box cover and voltage regulator assembly. Is there a terminal strip near the top of the control box that has B+,1,2,3 etc.? If so, you can connect the remote switches here. You indicated that when you operate the genset now, you leave the enclosure door open for ventilation. Would this still be done if the unit was started from indoors? I'm guessing the remote start/stop would be used as a convenience to keep from having to go outside. Also, do you know if your unit has a high temperature safety shutdown? If the unit was started without proper ventilation, it could overheat and damage the genset as well as possibly be a fire hazard. (You mentioned the door was wood, so I assume the generator enclosure is made of combustible materials.)

As far as the automatic transfer switch goes, this one is not compatible with your control system. Most ATS's use a 2 wire starting system, i.e. a set of dry contacts in the transfer switch close to start and run the genset. The contacts open to shut it down. This switch uses that logic as do most generators that are set up for remote start operation. Older Onan air cooled gens use a 3 wire starting system, whereas their liquid cooled units are 2 wire. (Never could figure out why they did that.) You cannot directly interface your genset controls to this ATS. Onan made 2 wire to 3 wire converters that were installed in their transfer switches when they were to be used with their air cooled gens. You may still be able to obtain a converter, but wiring could be tricky. In addition to the 2 to3 wire issue, you would need to incorporate a time delay relay that would energize the glow plugs for approximately 60 seconds before sending a start signal to the engine. The time delay would not be an issue if yours was a gas fired unit, but diesels like to warm up first before they kick over. As you can see, this contol scheme gets somewhat complicated. Also, an auto-start feature on your installation may present a safety issue like that described above.

Hope this helps.

Steve

[Billy J Shafer]

John if you remove the top of the control box you should find the remote terminal strip.It will be marked B+-1-2-3.Just hook you wires here for starting.You will also find a spot marked with an H this is for the glow plugs.Onan also made a constant glow plug heater.This was used to keep the glow plugs on at all times low voltage so they did not burn up.You will need a three wire start transfer switch or a converter to make it auto.

[Pentode]

I had to engineer my own remote start to work with my contractors model 12.0DJC and so far its worked quite well. Used a 5v 50amp computer switching supply that was for a mainframe however you could use a standard ATX supply rated at greater than 300 watts to maintain the cylinder head plugs and a set of relays for controlling start, stop oil pressure presence and knockdown of the glow plug supply when running. Only took 3 relays to do this and provide me with a 3 wire control for the xfer switch. It can be done but if you dont want to engineer your own you will need relays to handle the local switching of glow plug and start/stop inside the control box. I can write up my control at a later date if you're intrested, its somewhat complex but useful.

Pentode

[DieselCJ]

Thanks for the replies. The door does not stay stay open, there are mesh vents on three of the sides. Yes, there is a B+,1,2,3 etc bar. Is there a diagram to show me where to connect the wires?

Also, what does the third wire do running from the glow plug switch, I would think only two would be necessary.

-John

[Steve Dawkins]

John,

The remote terminals are as follows:

B+ Battery Positive - not used for remote applications unless you're going to remotely mount a battery charger.

1 Ground

2 Stop

3 Start

H Glow Plug Heater

All remote functions connect to ground. Start is terminals 1 to 3. Stop is terminals 1 to 2. The glow plug heater is terminals 1 to H. For your start/stop switch, use a single pole double throw (SPDT) momentary contact switch. Connect terminal 1 to the center terminal of the switch. Connect terminals 2 and 3 to the outside terminals. You may have to switch 2 and 3 to get the correct position; i.e. up for start, down for stop. For the glow plug or preheat switch, use a single pole single throw (SPST) momentary contact switch and connect the terminals to 1 and H. You can install a jumper at your remote switchs for the #1 wire. At the remote terminal strip on the generator, you should have a jumper between terminals 3 and H. You will need to remove this jumper when you install your switches. If you don't, whenever you push the remote glow plug switch, the generator will crank.

Make sure to use stranded wire for your remote connections. #18 or #16 gauge wire is fine. Don't use solid wire wire if you can help it. The vibration of the generator can fatigue a solid wire connection, causing it to break.

The third wire on the local preheat switch (the one at the genset) connects to the H terminal. When the local preheat switch is not pushed, this wire allows the H terminal to energize the glow plug relay. You do not need a 3 position (SPDT) switch for your remote preheat switch. Hope this helps.

Hey, maybe you can help me out. I posted the "DJC enclosure-noisy" posting recently. I'm trying to get ideas on building an enclosure for my DJC and hopefully make it a little quieter in the process. Could you possibly post or e-mail pictures to me of your enclosure? I'd be interested in seeing them. Do you feel your unit is very loud when it is running or does the enclosure absorb some of the nosie. Did you insulate the enclosure? Any feedback would be most appreciated. My e-mail is s.dawkins@cox.net

[DieselCJ]

Steve, thanks for the reply. Will I still be able to use the "local" (generator mounted switches) after I install remote switches?

I will try to post pics tomorrow of the enclosure. It is pretty simple, a 1/8" steel angle iron frame with 3/4" plywood sides and top with cedar siding. The thing is pretty noisy, but the nearest neighbor is about 100'+ away.

-John

[Steve Dawkins]

John,

Yes, your local switches will work as they do now. Just make sure to remove the jumper between 3 and H at the genset.

Out of curiosity, how is your genset interfaced with your home's electrical system? Do you have a manual transfer switch to isolate the utility and generator power, or do you have a "backfeed" breaker which you have to turn on after your main breaker is turned off and vice versa?

Thanks in advance for the pics.

Steve

[DieselCJ]

Here are some pics I took this morning.





-John

[DieselCJ]

[DieselCJ]

Alum. heat shield


I was thinking about making an additional support for the exhause, since it is only connected to the exhaust manifold, do you think this would help?

We got this unit new in 1993, each year I change the oil and filter with Rotella-T "synthetic" (blue bottle) 15W-40 and clean the air filter, the fuel filters are changed about every two years. Besides starting it every couple months, it probably only runs on average about 1-2 full days a year (during power outage). The maximum it has run was for about 36 hours a few years during a snow storm. Is there any other maintnance you would suggest?

Thanks,
John

[DieselCJ]

Here is the manual switch. The switch feeds the entire electrical panel. The UP position connects the panel to the lighting company, middle is off, and DOWN connects it to the generator (there is also a 60amp breaker mounted in a box next to the generator). I either wait until I see neighbors lights, or use a electrical tester to check for power on the power company side to determine if the power is back or now. I should ideally install a LED indicator light onto the power company side (if I could figure out how without getting shocked, lol).





BTW, in the past 12 years, this generator has not failed once

-John

[Steve Dawkins]

John, thanks for posting the pictures. I really appreciate you taking the time to do that. They give me some ideas for when I build an enclosure for my DJC.

Regarding the support for you muffler, I would recommend that you do something. At present, the muffler, exhaust piping, elbows and rain cap are all supported by the exhaust manifold. This weight coupled with the vibration from the engine can cause undue stress on the manifold and possibly crack it. When we install generators, we place a flexible exhaust connector between the generator and muffler/piping. The flex absorbs the vibration from the engine. The muffler and exhaust piping are supported independently of the generator. There is a company in Pennsylvania that we purchase steel flexible fuel connectors for generators that run on natural gas or propane. They also make flexible exhaust connectors although we have never bought theirs because the connectors are typically supplied with the gensets when we buy them. I'm sure this company would make an exhaust connector of any diameter and length that you need. Let me know if you want info on them.

I'm an electrical guy, and can help you with power and electrical control questions you may have. My DJC is the first diesel engine I've ever owned, so ithere's a learning curve for me. Over the years, we have installed many generators; several that used diesel engines for the prime mover. Once the installation was completed, maintenace and repair issues were handled by someone else. I will defer to others on this site regarding maintenance questions. "Hey guys, help John out here please. What should he include as part of his pm schedule and at what intervals?"

Thanks for the pictures of your electrical service. I am glad to see you have a manual transfer switch. With it installed, there is no way that utility power and generator power can be connected simultaneously and "buck" each other. Generally when this happens, the generator loses the battle and can suffer a great deal of damage, costing hundreds or thousands of $$$. This can include destroying the electronic voltage regulator, exciter diodes and even the main output windings. I saw a 500 kW genset once that was backfed with utility power. The main windings melted and formed solidified puddles of copper in the bottom of the stator housing. It wasn't a pretty sight. Sometimes, people don't understand the potential hazards involved when trying to interface a generator with their electrical system. When hurricane Isabel hit here two years ago, most of the area was without power for 1 to 2 weeks. Folks were getting desperate and trying any way they could to power their houses. I had several people come into my office during that time begging me to make a "backfeed cord" for them. Basically, it is a cord with two male plugs. One plug connects to the generator and the other one plugs into their electric clothes dryer receptacle. Power from the generator is backfed through the dryer circuit to the circuit breaker or fuse panel and distributed to other circuits throughout the house. Under certain conditions, this can be extremely dangerous. When people asked me to build these cordsets, I felt for them, but refused to do so for reasons of (their) personal safety and possible equipment damage. There could have been some liability issues for our company also.

Thanks again for the pictures. Good luck with your remote switches.

Steve

[ichudov]

I find it amazing that you have a complete monstrosity attached to your exhaust manifold, and it does not fail under vibration. Just hard to believe my eyes.

igor

[DieselCJ]

Originally Posted by ichudov

I find it amazing that you have a complete monstrosity attached to your exhaust manifold, and it does not fail under vibration. Just hard to believe my eyes.

igor

Yes, I should do something about the exhaustAnybody have pics of exhaust with flex pipe? I suppose I could build some sort of mount off of the plywood housing to support the muffler and steel pipe.

-John

[Billy J Shafer]

John any good muffler shop should be able to get you what you need.If not look on the net for shops that build exhaust systems and show them what you need.

[ichudov]

Originally Posted by DieselCJ

Yes, I should do something about the exhaustAnybody have pics of exhaust with flex pipe? I suppose I could build some sort of mount off of the plywood housing to support the muffler and steel pipe.

-John

I have exhaust with flex pipe for my Onan DJE, pictures for the time when enclosure was not painted and the exhaust was not yet pointing updards:

http://igor.chudov.com/tmp/onan/Diesel/Enclosure/

[DieselCJ]

Originally Posted by ichudov

I have exhaust with flex pipe for my Onan DJE, pictures for the time when enclosure was not painted and the exhaust was not yet pointing updards:

http://igor.chudov.com/tmp/onan/Diesel/Enclosure/

Thanks for the pics, how do you plan on supporting the pipe when you point it up?

Thanks,
John

[ichudov]

[QUOTE=DieselCJ]Thanks for the pics, how do you plan on supporting the pipe when you point it up?

I will put some 2x4x8 board up, then I would add some steel arm to the board, abd hand the muffler by a chain, tied to the arm. I want to avoid rigid connections, hence the desire to hang the arm on the chain. Also, the arm is there to avoid contact between the hot muffler and wooden board. The chain is a dog chain from walmart, already attached to the end of the muffler.

This will be sufficiently loose to withstand any vibration,

[Drew]

John -- Here's a diagram for an underground exhaust system from my Onan 10LS-103 (1kW) manual. If it would work on your setup, it might solve both your noise and exhaust support problems. Drew.