I am looking to install an additional relay module. I know it's larger than what people would recommend, but I went ahead and purchased the Cooper-Bussman 1540X-X-X RFRM Rear-fed Fuse & Relay Module here: https://www.cooperindustries.com/content/public/en/bussmann/transportation/products/power_distribution/power_distribution_modules/series_15400_rfrmrear-fedfuserelaymodule.html.
I looked hard at the 15300 series RTMR, but found I would probably need at least two more relays for what I plan to do. My question is powering the two 100 amp buss bars on the module. I want it poweredonly when the key is on, so can I use something like a PAC-200 200 Amp Power Relay like shown here: (https://www.amazon.com/PAC-PAC-200-200-Power-Relay/dp/B000CEBXRS
Having the powere relay switched on by the ignition, I figured I can run individual wire to the module itself.
Another question in doing it this way, would I put a fuse in between the battery and power relay (8 ga. with 200 amp fuse) or one between the power relay and new module (10 ga. with 100 amp fuse?
From the new module out, I pretty much have it thought out using fuses and relays to power my upgraded lights and switches. I just need to get power to the module itself.
I guess I could have the module connected directly to the battery and have all my switches powered by a relay powered by an ignition source...
Suggestions?
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Roll Tide!
Fuse or fuses within 4" (10 cm) of battery.
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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.
And add inline diode(s) to relays whose circuits you want reverse polarity protected.
Safety is another issue. Do you want redundancy in case your main relay bounces or drops out? Or its fuse?
But that issue exists with any vehicle installation, and few have any emergency backup systems. (I have an independent high-beam fallback, but other redundancies are based on relay or wiring swaps. But I don't have a relay that powers everything; that's all hard wired and fused.)
PS - I'd feel uneasy if relaying all my power. But the only time I have struck such a situation was in competition where the moronic organisers combined the "engine kill" with the "isolate battery" switch, hence requiring a break in the +ve battery supply. Hence for safety (and dual switch locations), a relay had to be used. AFAIK in practice, 2 parallel relays were used.