Redarc BCDC mounting

[nj swb]

Not long after I bought my NT I killed the Projecta dual battery isolator, and replaced it with a Redarc BCDC1220. At the time, I cobbled together a mount above the auxiliary battery, because this is where the Projecta had been installed by the previous owner:



Not a good idea. As can be attested by my long-suffering travel companions, in low range in hot weather the Redarc overheats and "de-tunes" its output. Low range hill climbs would see the battery voltage drop from above 14 V (bulk charging at 20A) to less than 13 V (slow charging - not what I bought a Redarc to do). Pop the bonnet, dribble some water over the Redarc to cool it down, and it would crank back up to full output.

So it needed to go somewhere cooler - either inside the cabin, in the air conditioning, or somewhere with better air flow, like behind the grille.



I used a couple of existing holes that mount a small plastic guard, and installed a couple of Rivnuts:



To that I mounted a custom designed 3D printed plate, and the Redarc is mounted to that.

So far, so good.

Too late, I realised that where I have mounted it won't work for the front mount intercooler I'm still hoping to fit, but there is room to redesign the mount to move it lower.



A job for another day.

At first glance, this mounting position appears to be behind a blanked-off section of the grille, but each section does have an opening to allow air flow. If I still have overheating problems I can cut these sections out.



If anybody is interested, the STL file (for the 3D printer) is attached (as a zip file).

[sharkcaver]

Of course, the closer to the battery the better (within reason), but engine bay mounting will produce issues as you found out. I'm sure where you have put it will be fine.

If it were me though, I would have cabin mounted it. Marginally less cable run and no issues with outside environment contaminants. I'm not convinced re their water proofness to be honest. As said, I'm sure it will be fine, others have done similar, just passing on my opinion that others may take on board when facing the same dilemma.

[2bad4u]

I started off with mine under the bonnet and then after having all sorts of issues (with de-rating) I removed it and put in an Intervolt VSR. This worked fine for a long time but I have recently redone all the wiring again. I removed the Intervolt and put the Redarc BCDC back in, but this time I mounted it in the cabin under the glove box. Everything is now working as it should and I have none of the issues I had before.

There are plenty of people who have mounted them up front like you have and don't have any issues.

[Jasonmc73]

My understanding is where you have placed it, would be as per where manufacturer suggests.

From memory they also like to see them mounted to a steel sturcture to help dissipate heat, act as heat sink.

[nj swb]

If it were me though, I would have cabin mounted it. Marginally less cable run and no issues with outside environment contaminants.

Yes, I did consider this, and figured there wouldn't be a huge difference in cable length - probably slightly less to under the dash, but I also had a bad experience with a power cable shorting to the firewall, which has left me a little "gun-shy". I also convinced myself that troubleshooting would be a little simpler if everything is available under the bonnet, rather than part of the system outside / part of the system inside. Ultimately, these are minor considerations, and inside probably is the smarter solution.

I'm not convinced re their water proofness to be honest.

Yep, every time I've pressure-washed under the bonnet I've expected it to cause me grief. But 6 years & counting...

Now that I've posted this, it will fail next week.

[nj swb]

From memory they also like to see them mounted to a steel sturcture to help dissipate heat, act as heat sink.

No argument that this would be a superior solution, but there aren't a lot of decent flat surfaces to mount on, to effect decent heat transfer. The first electronic dual battery controller I installed in Shorty was mounted to a huge finned aluminium heatsink (arranged vertically for optimum heat dissipation) and I also had trouble with that. I'm a slow learner...

The Redarc is spaced from the mounting plate, partly to clear the head of the plate mounting bolts, partly for better airflow, and the mounting plate also has a large hole under the Redarc - partly for better airflow, partly for less material / less printing time.

[sharkcaver]

Yes, I did consider this, and figured there wouldn't be a huge difference in cable length - probably slightly less to under the dash, but I also had a bad experience with a power cable shorting to the firewall, which has left me a little "gun-shy". I also convinced myself that troubleshooting would be a little simpler if everything is available under the bonnet, rather than part of the system outside / part of the system inside.

Good points there

[amec]

Just for fun i pulled the case off my Redarc BCDC1225 to have a look. The circuit board is encased in a very thick resin or something similar. Very waterproof.