relays

[bagmaker]

Hi wizards,
I have started on a re-wire basically to simplify the standard rat-bait spagetti factory that was installed by volvo, volgren and a half dozen other hacks in the last 3 decades trying, I suspect, to keep it functioning.
what style of relay would be good for my bus (24v DC). I have a left over heap of the standard cube automotive style (mostly 30a)but was wondering if a modern update is available? What about SSR style relays?
Want to use a half dozen or so for starter,air solonoids, pumps etc, mostly stardard heavy vehicle but some extra motorhome stuff.
I would prefer a gang style if available to keep it neat, most will need to be fused so any recommendations for fuses too.
They will be in the engine compartment so hot, dirty environment.

cheers

[Busman]

Baggie,
I would go for the cube type, easy to obtain, built for the environment (vibration) and pretty cheap compared to SSR's. SSR's are good where you want to control high currents, I would use them for anything over 30 amps myself.
There are some 12 place fuse blocks available now, even have a LED for each fuse, comes on when blown, they are great on a dark night, from experience, will usually distribute 30 amps or so with no worries. These are for blade fuses of course, but limit blade fuse use to 30 or below, there has been too many instances of melting and welding themselves in with higher current loads, instead of just blowing.
Having said that I have also used some SY4011 from Jaycar, DPDT high current relays for some things.
They also have some neat relays witha built in fuse, but only 12 V it seems.
Like others I suspect, I wish I had gone out and bought 100 of the same type, but as things get added sometimes you use what is at hand.
Why a relay for starter, probably pulling 4-600 amps for a few seconds, usually just 1 wire energizes the coil ?

[jon_d]

Yep, automotive 24 volt ones.

Built and designed for the environment.

[T1 Terry]

Why a relay for starter, probably pulling 4-600 amps for a few seconds, usually just 1 wire energizes the coil ?

Takes care of voltage drop from long cable runs, switches battery power direct to the starter solenoid so it fully engages. These are really handy for tidying up the relays http://www.ebay.com.au/itm/Relay-Mount- ... SweW5U5soL These link together to form a line as long as required and the wiring can be all tied up in a harness running along under the row of blocks and it looks quite neat and professional. I remember working on the Volgren tour bus builds when I worked for a Volvo truck workshop, a nice conversion but so many wires as they had an alarm for everything backed up with a warning light wired on its own circuit. Opening the back of the electrical panel was like taking the lid of Pandora's box, you couldn't seem to get them all back in again no matter how hard you tried, one would sneak out and pinch causing yet another problem.
Good luck with the rewire

T1 Terry

[jon_d]

I used those mounts when doing the Bedford.

Really good becuase you can easily remove the relay to isolate something when doing the wiring.

http://www.electroparts.com.au/index.ph ... r_product=

[bagmaker]

Thanks guys, I will check out jaycar Busman, have found the 10/12 bank fuse variety on ebay and will investigate. Dont really want the "all one side to neg or pos" option on those, more in line style like http://www.ebay.com.au/itm/10-Way-IP65- ... SwT6pVsvfh
but it looks pretty low end. Appreciate all your help. I have a heap of the relays and holders left over so will poach the best.

T1 Volgren seemed to be the marriage between the refined, elegant swedish metric volvo bride and rough-arsed Aussie imperial Grenda savage.

original wiring inside fuse box.jpg

From this I am down to some 20-something wires going from front dash to rear engine, including tail-lights. Thats all that will be needed.
I could have started a 2nd hand copper wire business except they were half cooked, dirty or corroded.
Old mate up the road (diesel mechanic) suggested at the start to "rip them all out and start again" -at the time it seemed crazy but now...... -could have just gone with electronic dash and a handful of control wires.
Such is life, all good fun.
At least I haven't run it out of diesel yet ....

[T1 Terry]

Thanks guys, I will check out jaycar Busman, have found the 10/12 bank fuse variety on ebay and will investigate. Dont really want the "all one side to neg or pos" option on those, more in line style like http://www.ebay.com.au/itm/10-Way-IP65- ... SwT6pVsvfh
but it looks pretty low end. Appreciate all your help. I have a heap of the relays and holders left over so will poach the best.

T1 Volgren seemed to be the marriage between the refined, elegant swedish metric volvo bride and rough-arsed Aussie imperial Grenda savage.

original wiring inside fuse box.jpg

From this I am down to some 20-something wires going from front dash to rear engine, including tail-lights. Thats all that will be needed.
I could have started a 2nd hand copper wire business except they were half cooked, dirty or corroded.
Old mate up the road (diesel mechanic) suggested at the start to "rip them all out and start again" -at the time it seemed crazy but now...... -could have just gone with electronic dash and a handful of control wires.
Such is life, all good fun.
At least I haven't run it out of diesel yet ....

You missed the in laws on both sides who know nothing about electrical stuff or hydraulics or how to flair the ends of radiator/heater pipes so the hose doesn't pop off and cook the engine, but are determined to each add their bid. Under sized wiring to electric fans resulting in half the wiring harness melting into a tangled mess, no fans and the eng starts to heat up, blows the hose off and no water to work the temp sensor alarm, but all the fuses have blown to them anyway when the wiring harness went up in smoke so the low water sensor didn't trigger. Destroyed engines with less than 10,000km on them and everyone pointing a finger to everyone else as to why it happened. Trying to explain to an "electrical engineer" that you don't put fuses in signal wires as there should only be 5v on the line at the most, therefore a short should set off the alarm, not blow the fuse and disable the alarm was like taking to a kindergarten class about quantum theory, trying to explain about rated cabling requirements and fuses should be less than the cable rating resulted in a "who are you trying to tell me" look, no hope

T1 Terry

[Busman]

I ran 3 x 13 core wires to the rear when we put the roof back on, recently I opened up the tunnel and added 2 x 7 core trailer wires as all the 13 core ones were used, add a few extra in there, you will not be sorry.

Me I prefer this sort of thing for a fuse distribution board, max 100 amps as oposed to 25 and the opportunity to have 2 seperate feeds if required
http://www.autoelectricsupplies.co.uk/p ... ategory/63

[Toolman]

I like the Blue Sea fuse and circuit breaker blocks that use the screw connection and not the blade terminals https://www.bluesea.com/#