Wiring New Instrument Panel

[AnchorageGuy]

There are instruments and there are instruments. The engine gages will typically be daisy chained. Ours are for the positive side but each has a separate ground. But for depth, wind, etc. these should always be wired individually. In a perfect world each would be wired to a circuit breaker switch. Most panels will not give you room to do each one but a sub panel would be your best bet. If that is not what you prefer, then a power strip supplying each instrument both positive and ground, connected to a circuit breaker would be the next best option. Daisy chaining these instruments will pretty much assure a failure of most or all just when you need them the most. Chuck

[David M]

Mark,
A traditional but waterproof fuse holder is probably your best best. Just make sure you put the fuse holders where they are accessible. You do not necessarily need a typical bus bar. You can take a terminal block, buy jumpers for it and create a bus bar...this will be smaller and take less space than a typical bus bar.

Please, wire your instruments in parallel, not "daisy chained" in series, as this would be a big mistake in terms of a voltage drop. Use heat shrink connectors and put either silicon grease or Tef-Gel over the bare metal ring terminals to stop corrosion.

Terminal block...


Terminal block jumpers



Waterproof fuse holder...

[LookingForCruiser]

You can "daisy chain" and still have things wired in parallel. I personally wouldn't, I like individual runs for everything, but the concept of "daisy chaining" isn't tied to a series circuit.

[CharlieJ]

You can "daisy chain" and still have things wired in parallel. I personally wouldn't, I like individual runs for everything, but the concept of "daisy chaining" isn't tied to a series circuit.

Huh? I don't understand your comment.

Charlie

[LookingForCruiser]

So you do a "chain" along the positive connections of all the devices, and then a separate "chain" along the negative connections. Depending on how the devices are connected, you could have two ring terminals on a positive post, or if they are spade-type connectors, you'd have to have two wires crimped together into the same spade terminal.

That's how Christmas lights that don't go out when one bulb blows are wired. It's still a parallel circuit, but the each later device is wired up to the previous one, instead of having a run back to the distribution panel. Positive to positive to positive to positive, and negative to negative to negative to negative.

[CharlieJ]

From a troubleshooting and problem isolation perspective, I contend that it is best to power each instrument separately from a B+ thru a fuse to the instrument and then back thru an independent B- to the auxiliary B- bus bar. All nicely handled by the Blue Sea blade type fuse block I referenced earlier.

Charlie

[LookingForCruiser]

Yes it's better to have direct runs, but it's not impossible to daisy chain. That was my only point. I personally only do direct runs. My electrical system is dirt simple, so it's not much of a hardship.

[cliffdykes]

Originally Posted by CharlieJ

From a troubleshooting and problem isolation perspective, I contend that it is best to power each instrument separately from a B+ thru a fuse to the instrument and then back thru an independent B- to the auxiliary B- bus bar. All nicely handled by the Blue Sea blade type fuse block I referenced earlier.

Charlie

BTW Charlie I have ordered the Blue Sea block and will be doing exactly as you suggest! Would you believe it is cheaper for me to order it and have it delivered from Annapolis than to buy it at the chandlers 20 miles down the road here in the UK?

Thanks again for the advice

Cheers
Cliff

[GordMay]

Originally Posted by LookingForCruiser

You can "daisy chain" and still have things wired in parallel. I personally wouldn't, I like individual runs for everything, but the concept of "daisy chaining" isn't tied to a series circuit ...

... It's still a parallel circuit, but the each later device is wired up to the previous one, instead of having a run back to the distribution panel. Positive to positive to positive to positive, and negative to negative to negative to negative.

Indeed.

There’s several applications where a parallel daisy chain is appropriate.
- A set of engine gauges
- A receptacle circuit