Managing ESPAR vs DumbAttack/ battery isolator,

[David_VT]

I need to keep one of my main batteries isolated from the ESPAR's power drain. Twice I have had dumb attacks and left the cab blower set too high. The ESPAR finally detects the voltage dropping off from both batteries and shuts down, but it is too late when both batteries have gone low at -10 degrees.

Anyone know of a reasonably priced isolator gadget that I can control from inside the cab? I've looked in the marine stores but thus far they look too expensive or too much trouble to install.

I thought about a big 12v contactor that would be online only when the key is in the ignition, but I am not sure if that would create too many problems for the cranking power issue.

I have also thought about running a third battery for just the ESPAR, thus isolating the heater totally from the main batteries. I imagine with some simple relays I could connect/disconnect this extra battery when the engine is running to help it charge up.

Any thoughts or other ideas I have not thought of??

thx

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99' SB 4x4 : DDI's, HOT PE, SPA dual gauge, ESPAR, Line-X OTR, Ladder bars, AMSOIL, etc (GPS,Cell,CB,... . )

 

[Alaskaskiff]

Try an RV supply place. There is an exclt on in Kingston, NY. A lot of RV/trailer folks may have similar concerns for power isolation & charging.

 

[HEMI®Dart]

Dave,
Leave yourself a big note on the blower switch. #ad


Have you had your batteries load tested? I have left my blower on medium for the 2 hour Cycle. My batteries don't even show the slightest drain.



[This message has been edited by HEMI®Dart (edited 12-30-2000). ]

 

[Joseph Donnelly]

Isolators are available from Warn etc. for use with electric winches. Another approach would be a big solenoid like for a starter. Low current to kick the solenoid, big contacts jump into place when the electromagnet or whatever is activated. I used an isolator from Warn if I recall when I had an earlier Ram with electric winches. I didn't want to risk running down both batteries, but the isolator allows both to be charged by the alternator.

 

[David_VT]

the big note idea already occurred to me... unfortunatly it blew off when I left the blower on too high #ad


Thanks Joe, (btw I sent you a request email on the sachs clutch).

To other 24v ESPAR owners, I missed the threads from others that told us the plumbing layout directions for the 24v engine was wrong as shipped in the box. Might explain why I am getting less heat than others report. Download the newest directions from ESPAR's website!!

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99' SB 4x4 : DDI's, HOT PE, SPA dual gauge, ESPAR, Line-X OTR, Ladder bars, AMSOIL, etc (GPS,Cell,CB,... . )

[This message has been edited by David_VT (edited 12-31-2000). ]

 

[HC]

Have you had your batteries load tested? I have left my blower on medium for the 2 hour Cycle. My batteries don't even show the slightest drain.

I second the motion. Even if the "high" setting on the blower added another 5 amps to the drain (not likely it would this high), your batteries should still have more than 90% of their original energy remaining after a 2 hour run, if both the batteries and your charging system are up to snuff. I'll bet one of your batteries is going bad, and you are really starting on just one battery.

 

[David_VT]

Thx for the input folks. I had not considered the battery life.
Hmmm maybe time for two Optimas. Which version is best for this application? I have a red top in my Chevy and have enjoyed it. Should I go to the deep cycle to help with these ESPAR drains???

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99' SB 4x4 : DDI's, HOT PE, SPA dual gauge, ESPAR, Line-X OTR, Ladder bars, AMSOIL, etc (GPS,Cell,CB,... . )
Green Monster

 

[jwgary]

YELLOWS!!! You can void a red top warranty in high drain applications like powerful stereos and other things like that. I would think that the Espar would be one of those situations.

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B I G O R A N G E AMBER-FIRE (BURNT ORANGE) / BRITE SILVER 2001(. 5), 2500, SLT, Q-CAB 4x4, SWB, AUTO, 3. 55, LSD, TOWING PACKAGE
ADD-ON'S: LINE-X, 1/4" STEEL LONGHORN HITCH COVER, WESTIN NERF BARS, YELLOW-TOP OPTIMAS

 

[EarthRoamer]

Take a look at your Espar manual. I have an Espar D1LC diesel fired air heater in my camper, and it only draws 2. 5 amps at the highest blower setting. The Espar uses the most power during start-up and shutdown when the glow plug is heated up, but this shouldn't be for more than a minute and a half for start-up and another minute and a half for shutdown. Total current for a 2 hour run-time is:
2 hours x 2. 5 amp = 5 amp hours
20. 8 amps x . 05 hours = 1 amp hour
total power used = 6 amp hours

this is a minimal amount of current that any decent battery should handle with ease.

As far as a battery choice is concerned, I highly recommend the Optimas. I have a winch connected to mine, so I use the Yellow Tops. If you have no heavy load items, the red tops provide more cold cranking amps.



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Bill Swails
EarthRoamer.com

 

[David_VT]

Bill,
The difference (I think) between the forced air ESPAR and the forced water version is that heating the cab depends on driving the RAM's cab blower via a relay in the ESPAR's controller.

The 'dumb attack' I mention is one of leaving the cab blower set to 'high'. Once the ESPAR starts, before long the cab blower is powered to whatever speed the settings were left at when you exited the truck.

Lately I've made it a point to leave the cab heater controls off so I could see the power drain of just the ESPAR. With no cab power drain, there is no problem running the ESPAR for 2 full hours even in the coldest weather I've seen thus far.

Pretty much sums up that the cab blower is the issue.

I am considering a cheaper solution for now. That being a relay that is latched at something like 12 volts so that the blower will drop off line long before the ESPAR sucks the battery down to 10 volts and thus point of no return for a cold morning start... .

The yellow tops will come eventually.