melted relay

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123abc
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melted relay

Post by 123abc »

im running a fg single fan normaly run on half speed now with new engoine and ac it struggles to cool i started to run it on high speed with a 30amp relay 30amp fuse with i think 50amp wire after 4 or 5 cut in and out cycles the fuse melted didnt blow just melted the blade fuse thinking maybe going to a 50amp relay and 50amp circuit breaker or should i go 70 amp just be safe apparently these fans draw big amps when started from dead stop
unilec5544
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Re: melted relay

Post by unilec5544 »

You need to determine what the current draw is, so if you know someone with a DC clamp meter or tong tester, you will know exactly the current draw. If not just drive in to a local auto spark and get them to tell you.
123abc
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Re: melted relay

Post by 123abc »

i have a clamp meter so just put it on and activate fanput it on the fan cable correct
hybrid
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Re: melted relay

Post by hybrid »

I'm running the big single fan on a regular relay without issue.
Is yours genuine?
123abc
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Re: melted relay

Post by 123abc »

no its not a genuine one i think i may have found the issue a couple of the terminals were a bit loose in the plug which could explain why the fuse was heating up, it was a fuse and relay in one im going too put a new relay and sep fuse on next week a 50a and fuse will do fine, i got 45 amps on my clamp meter but other forums have said they can be as high
as 70a on a hard start
Last edited by 123abc on Mon Apr 15, 2019 5:24 am, edited 1 time in total.
hybrid
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Re: melted relay

Post by hybrid »

I would have to double check, but pretty sure I have a 30a fuse.
123abc
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Re: melted relay

Post by 123abc »

going to an auto elect tomorrow to get what i need just checked again and it spikes to 54 amps on start then goes back to a steady 23a while running i think it just needs better quality terminals and relays to be honest the crap i am using is junk it was supplied with a fan kit i got a few years ago
66STNG
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Re: melted relay

Post by 66STNG »

It sounds more like a hot joint, which Causes heat. If the current was exceeding the fuse it would have blown, not melting it. Make sure all connections are tight with no play..
66 basket case
lukep6470
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Re: melted relay

Post by lukep6470 »

yep 30amp fuse, relay and single 18" fan, done 20,000 miles no problem.
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