Questions regarding a Blue Sea fuse block

[USMC CWO]

I'm preparing to install the Blue Sea 6-circuit fuse block myself. Since the maximum rating of the fuse block is 100 amps. should I install a 100 amp relay?

USMC CWO, all you need is a 30 or 40 amp relay. You will need to fuse the hot lead from the battery with a 30amp fuse - this is the number you work with.

That is where I have the question. If I am running, say 4 accessories, each pulling 15 amps, will it blow the 30-amp main fuse?

 

[Fred W]

I'm preparing to install the Blue Sea 6-circuit fuse block myself. Since the maximum rating of the fuse block is 100 amps. should I install a 100 amp relay?

USMC CWO, all you need is a 30 or 40 amp relay. You will need to fuse the hot lead from the battery with a 30amp fuse - this is the number you work with.

That is where I have the question. If I am running, say 4 accessories, each pulling 15 amps, will it blow the 30-amp main fuse?

Yep. Just add up the devices and that will be your total load. But I doubt you have 4 items each pulling 15 amps.

Formula for Power = I*E (current times voltage), so a 15 amp accessory at a nominal ~13V would consume 195 watts.

That's big power. 4 x 195 = 780 watts, way more power than the alternator is capable of pumping out.

 

[kaitsdad]

I'm preparing to install the Blue Sea 6-circuit fuse block myself. Since the maximum rating of the fuse block is 100 amps. should I install a 100 amp relay?

USMC CWO, all you need is a 30 or 40 amp relay. You will need to fuse the hot lead from the battery with a 30amp fuse - this is the number you work with.

That is where I have the question. If I am running, say 4 accessories, each pulling 15 amps, will it blow the 30-amp main fuse?

If you're running 4 accessories each pulling 15 amps, your battery will be dead long before the fuse blows. That being said.....

I have two terminal blocks, one switched (Blue Sea) the other always hot.

Both of these are fed by the same 10awg 30 amp fused run from the battery.

I run from my blue sea -

CCS100 Cruise

Heated grips

Warm n Safe heated jacket

Gerbings heated pant liners and socks.

Fuel pump for aux tank.

From the always hot -

Soltek HID lights (fed to their own 30amp relay)

Two 15amp Powerlet sockets.

All through a 30 amp fuse with a 30 amp rated relay.

Keep in mind that the useage of the farkles varies - It would be very difficult to exceed 30 amps draw at any given time - do the math - 30 amps times 13.8 volts equals 414 watts - and the rated outputs of the bikes are 490 watts for the GenI, 590 watts for the GenII. (or therabouts)

Having 4 15amp circuits maxed out would draw 60amps x 13.8 volts equals 828 watts - meaning your battery would very rapidly become a doorstop.

Fuses are for protection to guard against shorts in your wiring or in the farkle itself. Go with the 30amp fuse on your feed from +12v battery, and you'll be fine.

I'm preparing to install the Blue Sea 6-circuit fuse block myself. Since the maximum rating of the fuse block is 100 amps. should I install a 100 amp relay?

USMC CWO, all you need is a 30 or 40 amp relay. You will need to fuse the hot lead from the battery with a 30amp fuse - this is the number you work with.

That is where I have the question. If I am running, say 4 accessories, each pulling 15 amps, will it blow the 30-amp main fuse?

Yep. Just add up the devices and that will be your total load. But I doubt you have 4 items each pulling 15 amps.

Formula for Power = I*E (current times voltage), so a 15 amp accessory at a nominal ~13V would consume 195 watts.

That's big power. 4 x 195 = 780 watts, way more power than the alternator is capable of pumping out.

Yep, what he said.

 

[USMC CWO]

Well that makes things very clear. Thank you all for the information. It is much appreciated.

 

[Jazzzzz]

I run from my blue sea - CCS100 Cruise

Heated grips

Warm n Safe heated jacket

Gerbings heated pant liners and socks.

Fuel pump for aux tank.

From the always hot -

Soltek HID lights (fed to their own 30amp relay)

Two 15amp Powerlet sockets.

All through a 30 amp fuse with a 30 amp rated relay.

Just as a quick aside, can you actually run all of that heated gear + your Solteks at the same time without draining your battery?