simple 12v 30amp pcb?

I was wondering if it would be possible or if anyone has a link to something where I could make a relay board?

I have a Fiat spider

I do not have much room to put those huge bosch relays under the dash especially since i need 5 of them. Basically I have one for the cooling fan and fog lights that's a 30 amp relay,headlight low and high beam are 40 amp relay, now wanted one more starter motor.

But if I could build a small pcb board that would house the relays for half the size that would help a great deal.

Hello,

Wouldn't it be easier to just get a relay socket and try and hid the relay somewhere that has space? Just a thought. I'm a newbie so just thinking out loud. lol

Why not use the micro-ISO relays? Just make sure they are not the intermittent rated tyes like some I have seen.

But I'd suggest wires instead of a PCB due to the high current capacity.

The fact that you have a Fiat means you must be well versed in electrical and rust problems.
There's no PCB board made for standard relays, there are some PCB mounting relays, see Farnell, Mouser US or RS components UK.
Omron make "micro relays" as used by Ford, Mercedes and some Japanese.
Another UK firm, Raw Components make waterproof fuse and relay boxes which join together Lego fashion, but then that's the Italian failure, mounting electrical components unprotected in the engine bay.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

korrupt3dazn

"Hello,

Wouldn't it be easier to just get a relay socket and try and hid the relay somewhere that has space? Just a thought. I'm a newbie so just thinking out loud. lol"

Yea that would be easy I wanted to see if I could make something a little different basically complicating something simple and making a project out of it since the car is self is one. Thanks for the quick reply.

[B}Old Spark
"Why not use the micro-ISO relays? Just make sure they are not the intermittent rated tyes like some I have seen.

But I'd suggest wires instead of a PCB due to the high current capacity."

I was actually thinking of that last night that's a good idea and I can use them in a small grouping right next to the cramped fuse box. Thanks

howie ll

"The fact that you have a Fiat means you must be well versed in electrical and rust problems.
There's no PCB board made for standard relays, there are some PCB mounting relays, see Farnell, Mouser US or RS components UK.
Omron make "micro relays" as used by Ford, Mercedes and some Japanese.
Another UK firm, Raw Components make waterproof fuse and relay boxes which join together Lego fashion, but then that's the Italian failure, mounting electrical components unprotected in the engine bay."

Yea this one took a swim so now I had to buy new wiring loom and reconfigure some wires since they seem to try and use 1 circuit to power everything in the car or use 4 fuses just for the headlights. I am going to use those companies you stated and try and find some micro relays. I don't want the wiring to look like some of these cars where someone puts fog lights in and runs a power & ground wire from the battery over the engine and to the relay mounted to the front of the car, instead of making it neat and using the fuse box.

Actually what I mentioned about electrical problems under the hood along with rusting after 6 months is what killed Lancia in the UK.
I still don't trust ANY Fiats or Alfas even though now use AMP connectors.
Alfa GTVs are good for about 3 years before complete electrical failure.
Methinks you will end up going for a complete engine bay loom and fuse box.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Mount all relays terminals down, spray over with moisture retarder or lithium grease, enclose in a sealed box with the cable grommet underneath.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

"Actually what I mentioned about electrical problems under the hood along with rusting after 6 months is what killed Lancia in the UK.
I still don't trust ANY Fiats or Alfas even though now use AMP connectors.
Alfa GTVs are good for about 3 years before complete electrical failure.
Methinks you will end up going for a complete engine bay loom and fuse box."

Yea they have horrible problems with rust fortunately for me someone told me about por15 and some tricks for rust. There's also pretty common places where they rust if you a do a little research you can basically stop it in its tracks. It does however not touch salt nor rain and garaged. Bucket seats & 5 point harness & turbo are not really practical for driving everyday in NY.

But i really haven't had any problems with the wiring in terms of rust only the grounds which aren't that bad to fix if you zinc coat them, it only has 3 ground pods G1,G2,G3. The only real problem I see is the way the power is distributed like one fuse controls the blower motor and heater motor that's a big no no, also they use the lighting switch fuse to power the radio so when you turn the lights on it affects the radio also a big no no. I have created two more fuses by relaying lights and combining the high L with R fuse and Low L with R that way I can have some proper power to the components that need independent circuits.

Also just like any older car connections get dirty and over time break down I have cleaned every connector on the car which in reality took 1hr with harness pulled and coated with paste for anti rust. The other big thing is the starters use direct juice from the ignition yikes what a bad idea, you ever see the inside of those ignition switches talk about a weak link in Italian cars, the solenoid or starter gets old the amps go up and fry the contacts. Which i am going to fix with the relay.

You wouldn't happen to know where i could find a 131 stick shift housing? or a 132 banjo rear?

A bit of an aside...
The "James Bond Cars" doco with what's-his-pop from whatever that post-Braniac car show was on last night. He reckoned the Alfa (GTV?) was the ultimate Bond car (for the average person) costing a mere £4,000 - PLUS about £1,000,000 in maintenance LOL!

Mind you, that may reflect some owners...
A mate loves his Alfas but said the oft replacing of head-gaskets was a pain. How often - typically every 3 months! It turns out he would smear the gaskets in GRAPHITE to make them easier to remove! [ Mind you, they were my silly days too - like engine bores, I'd merely "wash" the head & block gasket faces with petrol, though I'd still get at least years from both. These days I get decades.) ]

Mr. Spyder, I tip my hat to you any other "tips" on protection and preparation would be teaching you to suck eggs.
And yes I forgot about the zinc.
Should have remembered back in the days of naked BMW, Mercedes etc. I used to paint every fresh drilled aerial hole with zinc primer.
One thought, wreckers yard, engine bay of vehicle using convoluted plastic tubing, get it!
You made me laugh about the Fiat 131, I owned one; an auto from 75-78.
Every morning after a rainy night my then wife had a laugh when I had to pull the splugs and cook them in the oven for a few minutes to make the mustard fire up.
Bought a 3 litre V6 Capri after that with my luck it had the Dagenham dustbin/Essex engine that the accountants got their hands on pre-production*.
The later Cologne 2.8V injection from Germany that made it's way into some US Fords was a much better engine.
*Prototypes were chucking out 300hp back in the early 70s, by the time it made production, the injection system became a carb, the 24 valve twin cam become an OHV with cheap gaskets and 136hp!
Thank you Henry F. ll.
Oh and new head gaskets every couple of years.


-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

I just returned from a wreckers. There was a 1989 Alfa. Unbelievable - it still generally used ceramic fuses despite having a couple of blade ATS fuses. To think I was critical of cars having ceramic fuses in the 1970s!

As to their diver's (RHS) side air cooled flimsy wire coiled resistor (maybe for the heater fan?) - OMG!!

I think it was Alfa (else Fiat) that were amongst the first vehicles with circuit breakers gown here. Alas they failed miserably - they hadn't factor in our higher ambient temperatures.


Anyhow, in retrospect, maybe I shouldn't be too critical of German vehicle electrics...?

Not that I don't have problems. Some of my Isuzu connectors became problematic after 25-30 years. Now I break and remake them at 10-year intervals as a precaution.

oldspark

“A bit of an aside...
The "James Bond Cars" doco with what's-his-pop from whatever that post-Braniac car show was on last night. He reckoned the Alfa (GTV?) was the ultimate Bond car (for the average person) costing a mere £4,000 - PLUS about £1,000,000 in maintenance LOL!

Mind you, that may reflect some owners...
A mate loves his Alfas but said the oft replacing of head-gaskets was a pain. How often - typically every 3 months! It turns out he would smear the gaskets in GRAPHITE to make them easier to remove! [ Mind you, they were my silly days too - like engine bores, I'd merely "wash" the head & block gasket faces with petrol, though I'd still get at least years from both. These days I get decades.) ]”

I bet it was expensive to maintain but so are Mercedes, Bmw, Jaguar, Austin Martin etc. I like Fiats for the peppy motors and looks, in comparison to having the same thing everyone else does, if that was the case there would only be Honda’s and Suabru’s on the road and what good is that. That being said I do drive a Mercedes and think it’s far superior to Italian cars, but for a little fun and some sideways action a hopped up Fiat does it for me and I still have money in my bank.

Yea the head gaskets I even replaced on mine but let alone it is 30year old car and the previous owner maintained the car, also since I upgraded to a turbo I needed a much better gasket. It still make me laugh sometime when people put crappy gaskets or parts they buy for really cheap and expect them to last (especially cheap Chinese). The second I had a problem with a Mercedes E300 I have, I automatically bought the gasket from the dealer because the 90’s E300 have head gasket problems which can be cured by a factory gasket if you buy anything else you better get ready to do the job again.      

howie ll

“Mr. Spyder, I tip my hat to you any other "tips" on protection and preparation would be teaching you to suck eggs.
And yes I forgot about the zinc.
Should have remembered back in the days of naked BMW, Mercedes etc. I used to paint every fresh drilled aerial hole with zinc primer.
One thought, wreckers yard, engine bay of vehicle using convoluted plastic tubing, get it!
You made me laugh about the Fiat 131, I owned one; an auto from 75-78.
Every morning after a rainy night my then wife had a laugh when I had to pull the splugs and cook them in the oven for a few minutes to make the mustard fire up.
Bought a 3 litre V6 Capri after that with my luck it had the Dagenham dustbin/Essex engine that the accountants got their hands on pre-production*.
The later Cologne 2.8V injection from Germany that made it's way into some US Fords was a much better engine.
*Prototypes were chucking out 300hp back in the early 70s, by the time it made production, the injection system became a carb, the 24 valve twin cam become an OHV with cheap gaskets and 136hp!
Thank you Henry F. ll.
Oh and new head gaskets every couple of years.”

In terms of preparation and “tips” meaning making passages for the water to flow and sealing the passages correctly! Not a miracle cure for rust.

The zinc coat is actually what I used on a 66’ Mercedes 230SL’s ground points it worked very well. I will actually be doing that for the fiat since it’s stripped.

Yea those 131 were problematic but what about mini coopers and there low distributors when it rained, Hair dryer anyone!
Or let alone the early 90 honda’s and those hall effect distributors always dying.

Yea head gaskets are one of those things now a days you can buy and it will never give you an issue especially Goetze and cosmetic gaskets. Unless of course the car has other issues then it’s the owner’s issue. It’s not like those cars had OBD2 and plug and play systems to almost tell you exactly what the problem is! They could run lean there whole life and someone would say hey the car runs great.

oldspark

“I just returned from a wreckers. There was a 1989 Alfa. Unbelievable - it still generally used ceramic fuses despite having a couple of blade ATS fuses. To think I was critical of cars having ceramic fuses in the 1970s!

As to their diver's (RHS) side air cooled flimsy wire coiled resistor (maybe for the heater fan?) - OMG!!

I think it was Alfa (else Fiat) that were amongst the first vehicles with circuit breakers gown here. Alas they failed miserably - they hadn't factor in our higher ambient temperatures.


Anyhow, in retrospect, maybe I shouldn't be too critical of German vehicle electrics...?

Not that I don't have problems. Some of my Isuzu connectors became problematic after 25-30 years. Now I break and remake them at 10-year intervals as a precaution.”

Ha I remember when I had an Izusu Trooper I would drive it to school everyone used to call it the Safari Wagon. All it had was glass all around but what a good truck and it was 5 speed and a animal in the snow. Still kick myself for selling it to a guy my father knew, guy put a plow on the poor 4cyl and ended up skidding into a tree RIP POOR TRUCK.

See - you too know the reliability of Isuzu! I rest my case!

LOL! But you do point out one of the biggest issues, namely the owner else the maintainer. Any vehicle can be doomed by the wrong part or maintenance etc.
I for one often read of a particular Isuzu engine which has gained notoriety as being unreliable, yet I have seen its torque doubled (at under half the RPM of the OEM peak torque) and power trebled with little modification and standard reliability. With modern pistons and bearings (meaning post-1990), that means over 200,000 - 400,000 km between significant rebuilds.
But that's by people in the know, not those that spend $thousands doing stupid things like they do to other engines.    

The sparts can also be a problem, though that doesn't necessarily mean Chinese - the Chinese do provide excellent products as many are well aware. (For those that underestimate that evolution and impact, have you ever heard the expression "Jap Junk" or "Jap Crap"? And does anyone doubt modern Japanese expertise or superiority in f.ex car electrics?) The engine I mentioned has one problem which is attributed to a head-gasket from a well respected local manufacturer.

And every part seems to have its cheap counterparts whether it be the inferior rivets that sank the Titanic or car parts. Not that "cheap" always means inferior (eg Chinese, or Fiat/Lancia) and some may even be superior, but how does one know? VIZ - There are unbadged normals versus those unbadged becausethey are seconds.


I seem to be lucky in that I meet people in the know whether it be those that permanently fix BMW boxer head oil leaks or their slipping clutches, or extract amazing engine power without even opening up the engine.
I too have contributed in many ways but introducing better and cheaper methods or debunking old methods - not that everyone is receptive to the enlightenment.


I too have my sacrificial joys - eg, a 1972 Ducati GT750. It cost me a mere $400 and $650 total on the road. It's pre-trip timing and general check over continued until I installed a Lucas-RITA ignition. After that I'd treat it like a Jap bike - just start and go without any checks. And yes, that was a Lucas system, but I understand that Rita to Lucas is as Macintosh was to Apple - ie, "bought" in.
And that was a cheap bike that beat others of its type (I had Mikuni carbies!) and even kept up with Jap bikes of 1100cc (after dropping 2 bike lengths at the start - damned slipping clutch!). But after it went to a reputed shop for new big ends... let's just say costs skyrocketed and she never recovered.


Each poison has its own kicks. My duke too had its woeful electrics and ceramic fuses - its switchgear is now off an old Suzuki (just as Moto-Guzzi later did).   But its engine should have been bullet proof. Unfortunately the bevel-gearing's high production cost led to a skimping of their hardening and variations in their assembly compromised quality.
Most Italian things had excellent peak performance engines etc, but electrics and poor body metals (hence rust) let them down.
English stuff often had amazing innovations and often too a peak performance but parts variations (versions) and maintenance difficulties and electrics could be a problem.

But yeah, each has its Zen.
And unfortunately there are those silly enough, else clever and bored enough, to enjoy a bit of individualism.


At least I don't feel guilty about hijacking this thread. It's been fun finding like minded. Even the old Hall sensors - though I have often dealt with modern Halls and arguments that they - like optics - are "digital" unlike reluctors which are "analog" and therefore less accurate LOL! Then comes their issue of reliability.
I have other ridiculous discussions & arguments, but they seem confined to my locale and not OS or at least not on the12volt etc (tho one classic self-defeating discussion on mp3car relating to "diode" battery isolators comes to mind).


Ah well, I'd better get back to my reality.
And your relay issue....

Would these Relays work (https://www.theelectricaldepot.com/micro-relay-12v-spdt-20-amp1-each-440.html) There micro 20 amps relays.

Considering that I gave enough compensation for voltage spikes for the components.

I used a Power Probe connected to a battery and probed right to source using a Fluke multimeter and a fluke high current probe.

H4 bulb Low(55watt) and high beams(60watt) initially spiked at 7amps and 6amps this being of course its right to the bulb not the fuse box. So for 2 light call it 15amp to be safe?

H3 bulb(55watt) Fog lights initially spiked to 5Amps, so both 11Amps to be safe?

Cooling fan(Manufacture spec. rated it at 110Watt(8.5amps) I got an initial spike at 17amps but running stabilized to 7.45amps.

The Starter motor however would have to be a heavy duty relay it is rated at 1.3kw which i came out with 110amps @ 12volts.
Any ideas on a compact relay instead of a big ford style solenoid?

I'm not sure if that relay is continuously rated, though it probably is.

But you are not putting those relays under the dash are you? That essentially defeats the purpose of having relays, plus makes the installation (wiring) a nightmare!


As to the starter, the 110A is carried by the starter's integral solenoid which not only mechanically engages the starter gear, but also closes the contacts to the main battery. (Unless it's an old Bendix-spring type starter, but I doubt even Alfa is quite that primitive.)

Starter solenoids usually require about 20A to operate, though they will consume double that current until the solenoid engages its contacts or if the solenoid to battery +12V is disconnected or bad.
However since such relays should be in the engine bay (as should the others), a larger 40A relay should not be an issue. Traditional Bosch type mini-relays are available in 40A, 60A and even 140A (though >80A is usually a bit bigger), although a 30A relay should suffice unless the battery to solenoid is disconnected. (Relays typically withstand typical short-term current surges and over-currents that are higher than their nominal rating).

Yes I will be putting the relays under the dash I don't like the look of them in the engine bay, makes it cluttered for such a small car especially with wires dangling all over. They will be right near the fuse box so wiring should be fairly easy.

There is a C16 connector which is a main connector from the battery to distribute power I will be fusing the leads from there for my constant power and ground all of them individually to one ground point instead of in series and since the wires have the "signal" wires right to the fuse box its as easy as disconnecting them from there and shoot them to the relay and out to the engine bay for the devices.

The car at the moment is stripped, so making a bracket for the relays and rewiring a few circuits I don't like shouldn't be a problem. Also putting in Mercedes vacuum locks and window regulators, the Fiats are small and hardly work right with the pulley wire system, scissor system is far superior.


If I just bought 30 amp mini relays that should be sufficient for everything then? Having a little more amperage shouldn't hurt anything? The relay should only have to use whatever draw amount is being put on it right?

Having extra relay capability (capacity) is fine.



keep in mind that dragging heavy wires into the cabin and out again is one reason relays are used - using relays means only one thin cable through the firewall etc instead of 2 thick cable capable of carrying the full load.
And using cabin mounted relays usually means about 3-5 times the power-cable length, hence needing thicker wire (ie, 3x to 5x less resistivity) for the same voltage drop.

My thoughts entirely.
Sealed plastic box in the engine bay.

-------------
Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.