Amperage ratings of automotive relays and switches???? 1

[bill190]

Everywhere else in the electrical world, electrical components come with amperage ratings on them. And the electrical specifications of the component is printed on the product packaging or there is an insert with specifications on it. And this information is on the manufacturer's web site.

But NOT with automotive parts! Nothing but a part number on the packaging for switches and relays. No part specifications on the internet anywhere!

Automobiles are becoming quite complex electrically and technicians need to know this basic information.

Anyone know where to find electrical specifications for automotive switches and relays?

Or is there a particular automotive parts manufacturer who has "joined the internet age" and has this information on their web site for their parts?

Here is an example of typical relay specifications from parts suppliers "in the rest of the electrical world"...

http://www.magnecraft.com/library/section8/105A_172DIP.pdf

 

[mcgyvr]

http://relays.tycoelectronics.com/auto.asp

??? specifications all over the place...
Are you just talking about walking into an auto parts store or something?

 

[LionelHutz]

There's typically 2 levels of parts available. Junk unrated ones and good rated ones. If you have a more critical application then you have to find the good ones, they're out there.

OEM parts don't need the ratings. These parts were designed to work for their intended purpose (well, hopefully they was) in the car they were designed for. Anyone who's fixing cars will just buy the new component and install it.

If you're adding or changing the car then look for the good parts. I know you can buy Bosch style 30A relays fairly easily. As for toggle switches, you'll likely have to go with a "crossover" switch that have ratings beyond just 12VDC, such as 250VAC rated or 120VDC rated as well.

 

[patprimmer]

I agree with Lionel

Anything worth the time it takes to fit will have a rating on it.

240 volt rated switches work fine so long as they are also rated for the required amps.

Truck aftermarket parts suppliers are often much higher duty or better built than car parts

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[bill190]

Yes adding or modifying things in vehicles. Sometimes replacing existing in older vehicles.

Perhaps you want to change to HID headlights.

Or maybe add a fan for the radiator.

Or add fog lights.

Or add a relay for "ignition on" 12V power to a trailer.

Or maybe it is an older vehicle and the headlight relay part is no longer available. Well there are plenty which will do the job sitting in the auto parts store (with a bit of connector rewiring), but what are their specifications?

You can't just walk up to an auto parts counter and ask for a 12VDC continuous duty rated SPDT relay which has contacts rated for 30 amps! They want to know what year vehicle, etc.

And with the newer vehicles and all those computer modules, it is a good idea to not tie into any existing circuits. Rather install your own "ignition on" relay for what you are installing. Just need the right specification relay is all! And ????

Anyway thinks for the above link!

 

[GregLocock]

I'll point out the bleeding obvious, since you seem unable to take a hint.

P&A operations exist to support the design as produced by the manufacturer.

There is no advantage to the manufacturer in printing the spec of the part on it.

If you want to buy specced parts go to an electrical part supplier, not a manufacturer's P&A operation.

Which bit is hard to understand?




Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[bill190]

Well I should think someone in business would want to seek out profit avenues anywhere possible?

At least that is what I was taught in college.

A little extra sales here, a few extra sales there, a little sideline business somewhere else, then you might get your rent or electric bill paid by the extra revenue. A good thing in business!

But I suppose the automobile manufacturers and their suppliers have so much profit dripping form their coffers lately, that this would be a waste of time?

 

[GregLocock]

You weren't paying attention in college.


Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[thruthefence]

Often the racing equipment vendors will have specifications for this sort of thing. Pegasus Racing comes to mind.

Most people who go into auto parts stores these days couldn't care less about the 'voltage drop across the switched contacts' when all they want is for the horn to honk. And they really don't want to pay $75.00 for a milspec relay, when a $3.00 Chinese-made Bosch clone honks just as well.

Back in the pre computer database days, you could find some old guy behind the counter of a auto parts store, surrounded by huge reference books, provided by the various vendors, that indeed have 'specs' in them, if you knew where to look.They would usually assist you in 'matching up' your needs with what they have on the shelf. No more. The Ma-N-Pa auto parts store, manned by a knowledgeable clerk, has gone the way of the Dodo.

 

[bill190]

Actually in the do-it-yourself home electrical areas where everything is marked with amps/watts, quite a few people are aware of amperage and how much you can put on a circuit.

They don't know the exact numbers, but quite a few people know enough to ask.

Actually they will even point out inconsistencies such as 15 amp outlets and switches on 20 amp circuits. And they are concerned about this! (This is ok per the U.S. national electrical code BTW.)

But it is because these things are marked that people notice.

The same people work on their cars and I would imagine they would notice these things as well if automotive parts were marked too.

BTW I'm not suggesting that each part be marked, nor am I suggesting that any of this information be placed on the product packaging. I realize this would cost a young fortune.

I do think it would be a good idea to place the specifications for electrical parts on the internet though. Everybody else is doing this these days.

 

[patprimmer]

Well you could track down and seek out every manufacturer of these parts and demand they run their companies to conform to your desires. Good luck. Did you intend doing anything else with the rest of your life or would the obvious success you can expect from such an endeavor be satisfaction enough.

Now to another major social injustice. What can I do to stop the Sci-Fi channel showing mysticism as Sci-Fi. To present Buffy the Teenage Vampire Slayer as Sci-Fi is tantamount to fraud.



Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[bill190]

Well I asked and received!

This information *is* out there, you just need to ask.

This is the list so far...

Tyco Electronics Automotive Relays & Modules Datasheets

http://relays.tycoelectronics.com/auto.asp

Bosch Relays and Tractive Electromagnets

http://www.bosch.se/content/language1/downloads/Relays_Catalog_2005_2006_eng.pdf

Vehicle Wiring Products - Relay Specifications

http://www.vehicle-wiring-products.eu/VWP-onlinestore/relays/relays.php

Vehicle Wiring Products - Switches rated at 15 amps

http://www.vehicle-wiring-products.eu/VWP-onlinestore/switches/modular.php

 

[MacGyverS2000]

Actually they will even point out inconsistencies such as 15 amp outlets and switches on 20 amp circuits. And they are concerned about this! (This is ok per the U.S. national electrical code BTW.)

15A outlets are keyed to only allow items designed to pull 15A or less to plug into it. 20A outlets are keyed differently, and you can only plug a 20A appliance into a 20A outlet, not a 15A outlet.

In that same vein, you can put a 20A outlet on a 15A circuit as long as the circuit has the properly rated breaker (15A). It dumb, but it's legal, because the breaker will properly trip if you attempt to pull more than 15A for any extended period of time.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[LionelHutz]

You can't just walk up to an auto parts counter and ask for a 12VDC continuous duty rated SPDT relay which has contacts rated for 30 amps! They want to know what year vehicle, etc.

Well you're obviously going to the wrong place. Why would you even think a "replacment or OEM parts" store could help with custom work?

Try an electrical supply house which supports contractors but also has a walk-in counter. I'm sure the guy behind that counter could find you a quality toggle switch with a published rating. Don't cry though when it costs $15.

This place has been around for a while now keeping up a good business.

http://www.painlesswiring.com/

Honeywell sells many types of quality switches.

 

[bill190]

Thank you.