Multiple Amp Relays

I know i can use a SPDT relay for the amps. but i also intend on using fans.  should i use a seperate relay for the fans?  and how should i wire both relays to the remote wire from the head unit?

 for the amps?

for the amps and fans?

400/12.6 = 31.75amps
150/12.6 = 11.90amps
150/12.6 = 11.90amps

now should i put the 400w amp on a seperate 40amp SPDT relay from the others?

im unsure how to determine how much power is coming from the head unit.

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Proudly stuffing large packages into small boxes since 1983.

If I interupt your diagram correctly, you intend to use a relay to provide power to three amps. Wrong. Use one relay and hook terminal #86 of it to the trigger/remote wire from your radio. Terminal #85 to ground. Terminal #87 to a fused (5 amp) source of battery power. Terminal #30 to each amps trigger/remote wire. You can also use this to power fans. Add up the current requirements of all fans, add 1 and use this value for your fuse on the relay supply wire. If your diagram is correct and each amp only requires 0.3 amps to work, then a 5 amp fuse is fine to use. Each amp must use a heavy gauge power wire fed from the vehicle battery. For most multi-amp set-ups, it is advisable to run a fused heavy wire off the battery (4 gauge) to the amps. Use a fused distribution block at the amps location, to split the cable into 3 smaller (8 gauge) wires to supply each amp with power. Use the same gauge wire to ground each amp. Install a fuse/breaker equal to the sum of the three amps current requirements within 18 inches of the battery. Each fuse at the distribution block should match the amps current rating requirements as ditacted by the manual for the amp.

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sparky

yeah i got the power right.  just wasnt sure about how much power the amps use through the remote wire; or how much power goes through the remote wire.  thanks.

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Proudly stuffing large packages into small boxes since 1983.

oh also, my dist block has 4 outputs, can i use the 4th output as the 12v source?

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Proudly stuffing large packages into small boxes since 1983.

If I interpret your second pic correctly, It should work. If the 3 wires coming from the relay and going to the amps are for the remote turn on only, then yes, that is correctly.

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"People with mullets live 40% longer"   - Ricky Bobby

As much power goes through the remote wire as is demanded by the loads.  Since remote wire is usually 20 gauge, you know there isn't a lot of amperage expected.

The amps will use less than 200 milliamps each (.2 amps).  Add up the amperage ratings of the fans and add them all up.  The output of the block would be fine as the 12 volt source.  Here is a diagram that the12volt has provided on this site:

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

guys thank you all for your help.  i greatly appreciate it!

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Proudly stuffing large packages into small boxes since 1983.

i bought two of these fans... now im curious to know... it has 3 wires, red black and blue.  i would assume red is hot, black is ground, and blue...? maybe thats the turn on?

https://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=259-122&Cfid=1487972&CFTOKEN=72917684

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Proudly stuffing large packages into small boxes since 1983.

The additional wire is for data. These style fans are commonly used with computers and this data wire can allow the computer to monitor the rpm of the fan and control the speed to provide more or less air flow as needed. I'm sure there are audio components that take this plug directly, but you can just cut the plug off and use the black wire as your ground and the red wire your 12V+.

It doesn't sound like the additional data wire is going to be of any use to you. You can just cut it off and it won't make any difference. I do this all the time with similar fans.

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2 x DD9515f's, Digital Designs Z1 amplifier

Make sure you let us know how much NOISE is made by these two tiny little fans....those things are HUGE....