isolator or separator for :06 chev express 190 P 07 C roadtrek?

CareyM-ClassB

Member
Joined
Apr 11, 2011
Posts
16
Location
PA
is this model the Hehr isolator diode type isolator. ? 4 post isolator w 5 wires connected, one being the voltage sense wire.

or is this Sure Power diode type Isolators or Separators? previous post said " At some point RT started using Sure Power separators but that came well after '02. "

all info wore off the original label. we found the lack of house battery being charged from the engine alternator was due to a bad sep or iso unit by testing w fluke clamp on dc am meter , zero amps were getting to house battery.
unfortunately the incompetent cherry dealer diagnosed it as 'bad alternator', and never tested that charging amps off the alternator were flowing just fine into the engine start batter. dealer charged me for an alternator replacement , I demanded return of the supposedly defective one which Bech tested just fine.

here are photos. #1 is worn label and top. Lower leftmost stud on vertical front panel has 1 4 AWG black wire running to engine battery hot, it is the only wire to that battery. . there are 2 terminal plates with studs on the unit's top surface , neither connects to the engine battery.

if anyone has a wiring diagram, that would be very helpful .
 

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The picture does not show a Hehr diode isolator. I do not know what it is.
It sure looks like a Herr isolator to me. The photo angle is not the the best, but you can see the 3 terminals sticking out and the self resetting breaker on top. My 2008C210P ( both upfit and chassis are 2008) has a red Herr isolator just like the one in the picture. There have been questions about when RT switched from isolators to seperators…apparently it is not a consistent change over. I suspect that my 2008 might have been one of the last.
 
I had the same issue with my 05RT210. The dealer installed a new alternator and we took off on our 1080 mile ride home. On the second day the alternator gauge showed low voltage. We stopped had dinner and when we started again all was good. It acted this way again the next afternoon. When I got home I took it to O'reilys (where they bought the replacement) and they gave me another new one. I installed it and that didn't help. Sooo after much research I replaced the isolator (which is the red item in your picture), the two circuit breakers (which are mounted on top of the isolator in your picture). These did not fix the low voltage problem either. But the isolator had what looks like a burn hole in the top and needed replacing anyhow. The item that fixed the issue was the black relay at (least that is what I think it is) that is mounted on the far right side of the isolator.
Here are the part numbers
Isolator - #33-20 ( it replaces all older 33-30 models), from Powerline hdpsi.com
Relay - 896H-1AH-C1 12VDC 50Amp 4pins SPNO Automotive Power Relay, from Amazon
Circuit Breaker - 54-250PLP I believe these can be purchased from Powerline also
The people at Powerline were very helpful, they made the original Isolators for RoadTrek. They will set you straight. I have not had any issues since. Hope this helps.
 
I got fed up with the original equipment isolator (separator? I can never keep them straight) failing to charge my van battery, so I disconnected the wire to the house battery and stumbled along with solar and plugging in. Then, I installed a solenoid. It took some headscratching where to connect things but for five years I have had zero problems.
If you want, I can post pictures and an explanation.
 
On rereading the above, I have a correction. I initially disconnected the wire to the ALTERNATOR, which immediately fixed the "failure to charge the van battery" problem. Of course, my fix immediately exchanged it for a "failure to charge the house battery" problem.
 
Isolator/separator have been confused since they dreamed them up.

I think most places are calling the relay style, auto isolating, one "automatic charge relays".

The eliminate the on/off switch remembering and charge both coach and chassis batteries plus isolate them from each other when the engine isn't on. They work well for most people and very easy to wire into the system.
 
I got rid of the SurePower separator- the dang thing got way too hot and eventually started to malfunction. It's a non-latching relay, needs constant power to activate. I think some of them were recalled. I got concerned about it shorting out.
Installed a Blue Seas 7622 separator with remote selector/indicator switch, 2010 RT 210P. Lifetime warranty, works flawlessly, allows for auto or manual connection/separation. It's a magnetic latch relay, very low power draw, I think a safer separator. No issues with engine heat.
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I got rid of the SurePower separator- the dang thing got way too hot and eventually started to malfunction. It's a non-latching relay, needs constant power to activate. I think some of them were recalled. I got concerned about it shorting out.
Installed a Blue Seas 7622 separator with remote selector/indicator switch, 2010 RT 210P. Lifetime warranty, works flawlessly, allows for auto or manual connection/separation. It's a magnetic latch relay, very low power draw, I think a safer separator. No issues with engine heat.
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I did the same years ago on my Roadtrek 02D190P. Never had any issues with it. I'm about to do the same on my newly purchased RT 04C190P. From your picture it looks like you didn't reuse the existing circuit breaker in line between the coach batteries and the Blue Sea solenoid. Is that correct? Thanks.
 
We used the same setup when we had parallel dual alternators, but now just use it as a safety on/off manual switch with indicator light. With the standalone there is very little reason to shut off the connection to the batteries as we turn off the alternator with the Victron battery monitor internal relay when charging is done, automatically.
 
I did the same years ago on my Roadtrek 02D190P. Never had any issues with it. I'm about to do the same on my newly purchased RT 04C190P. From your picture it looks like you didn't reuse the existing circuit breaker in line between the coach batteries and the Blue Sea solenoid. Is that correct? Thanks.
I left all existing circuit breakers in place. They're a bit further left on the firewall, not really visible below the large wire loom. And to date, the blue sea unit has worked perfectly.
 
I left all existing circuit breakers in place. They're a bit further left on the firewall, not really visible below the large wire loom. And to date, the blue sea unit has worked perfectly.
I left my circuit breakers as well, I was just wondering if I didn't need to.
This modification allowed me to jump start my van on more than one occasion and when boondocking for long periods I was able to keep my start battery topped off.
 
I've built a lot of wiring harnesses and my #1 requirement is that every circuit is protected by fuse, cb or fusible link. So I'm skewed towards maybe overprotecting circuits :).
In this case there were cb's installed already so I was very reluctant to remove them once I could see how the circuit(s) were routed. There's also cb's underneath the coach on the genset circuit. So far no issues with any overloads/shorts.
I do like the remote switch provided with the blue sea relay, makes it very easy to connect or isolate vehicle and coach batteries safely. I know I can use coach batteries as a jump start if needed but I carry a jump pack as well.
 
If interested in trying a Blue Sea solution - I have one that is excess to my requirements. I did use it for several short trips and it performed flawless as expected. I have moved on to a B2B charging setup so no longer required.

Drop a note if interested.

Cheers - Jim
 

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