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TR2/3/3A 30a 5 pin universal relay

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Jedi Knight
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Noticed I had no brake lights yesterday.I use a micro switch and a relay.
The universal Standard brand ,Napa sourced,made in china ,bosch type 5 pin relay was faulty.The coil pulled in,and the switch closed but the resistance was high.New relay problem solved.
Whats got me wondering is this is the second relay since I have been on the road,5yrs and under 14k miles.
Are the relays just inferior?Should I get a genuine Bosch replacement?
Thanks
Tom
 
So the question is if Bosch makes better relays than the Chinese? Judging from your experience, I believe that’s a rhetorical question.
 
Thanks.Im not sure if my experience is typical.The Boschs are made in Portugal and Germany and I am not sure if thats even relevant to quality,but I wont buy the Standard Napa brand if there is a next time.
Tom
 
I don't believe Bosch even makes relays any more; they sold that business off to Tyco some years ago.

Myself, I'd just chalk it up to bad luck and install another cheap relay. Seems like it's "luck of the draw" with almost any component these days, the Chinese are actually capable of making good quality parts if properly motivated and other countries (including the US) are quite capable of making cheap junk. I bought a bunch of them on flea-bay for something like $2 each (including socket and pigtail) and none of them have let me down yet. This one has been in service over 30 years and still going (although the wires have been replaced since then)
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Maybe you have that dry Southern Cali air working for you not our high Humidity NJ air.
Funny when reading threads about ammeter vs voltmeter(I went with voltmeter),I remember you said one advantage of the ammeter is you can see it tick when you apply brakes to easily indicate the brakes lights are working.I thought I dont really care about that.
I would have most likely noticed the failure sooner with the ammeter.
Thanks
Tom
 
Well...I had an XJS Jag that used to eat relays. There were at least 30 on the car. The ones from Spain tended to do just fine, at least I never replaced one of those. The no-name relays went like popcorn.
 
Back in 1978 I worked for a coil winding machine manufacturer. We supplied Bosch 2 automatic winders. Would spit out tag wrapped, soldered and wound in a cellulose insulation.
Can't remember how fast it ran but it did wind at 30,000 turns per minute 6 coils at a time.. Neat machine. All pneumatic controls.
Bosch did send us a nasty letter saying that we would have an engineer, draftsman and technician on site to fix the machine so that when it got out of sequence it could be reset in minutes not hours. Also the circuit diagrams had to be a true representation of the machine.
It took a while but we got it in the end and they ordered more machines.

David
 
When I buy those relays, I try to find ones that are a name brand, so there is a data sheet with specifications they must meet. Without that, it's likely that the consistency is poor, which could explain a lot of those cases where some fail and others last forever. I don't have a problem with Chinese-made relays; I used Song Chuan relays in my MG TD restoration, but made sure I had a data sheet for them.

One problem with all these relays is that their current ratings are not in amps; they are in a different unit, known as liar's amps. My Song Chuan micro relays were rated at 20 amps, but per the data sheet, the lifetime drops by a factor of 100 if you get close to that current level; 8-10 amps is a more reasonable limit. Even this may be optimistic, as it applies only to resistive loads; inductive loads will fry the contacts much more rapidly. Also, it depends strongly on how quickly the contacts open or close, and that depends in turn on the circuit driving the relay. It's common, for example, to put a diode across the coil to prevent an inductive spike of voltage when you cut the current to the coil, but that slows the operation of the relay and the life expectancy drops further.

If you look around a little, you can find relays that are sealed and can be used in exposed locations. If you do that, however, be sure that the connections are similarly weatherproof; they exist, but you may have to search a bit.
 
Here is my most likely warped logic. I can buy 10 Chinese relays, shipping included, for about the price of one brand name unit. They can be changed in a minute. I guess I was lucky as my 2 year old bag of 10 relays still has 7 in it and I gave one away and put another in the glove box.
Tom
 
Yes Tom, I saw relays priced for 10 for what I paid for one,11 bucks.
Looking on the net led me to chinese wholesaler.Relays are 30-80 cents ea. in lots of 500,so the production methods must be pretty advanced.
I should add one to my tool bag.
 
I pay $4-$5 for name-brand relays. They're just not an expensive part; in the costs of these cars, that's a sneeze in a hurricane. So, I'm good with it.

That 30-cent figure is absolutely astonishing!
 
That reminds me of the time I bought 5-$10 wrist watches on Canal street in New York. As are most gear heads, I am terrible with watches...always scratching the crystal, no matter how careful I am. I figured I would buy 5 knock off rolex’s, for 1/2 the cost of a decent watch, and I’d come out ahead! Didn’t happen. All 5 knock offs were broken in 2 weeks. They didn’t last long enough to scratch the crystals.

I filed it under, “it seemed like a good idea at the time!?!”
 
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