ST85 vs. other c/o GP Relay?

[donalloy1]

I know this has been covered many times! Might be worth another run?

General population seems to agree that Napa ST85 is one of best GP Relay's to use on CUCV platform.

My GP Relay decided to give up ghost this week. So it's time to make sure I am replacing with the highest quality for longevity. She has been so dependable. Want this to continue!

Local Napa store has ST85 on shelf. According to Napa web site it is only good for 12 volt systems? Any thoughts... DMLII sends respectfully

 

[MarcusOReallyus]

According to Napa web site it is only good for 12 volt systems?

No problem. It's only dealing with 12 volts.

1. Stock vehicles: When the relay is OPEN (no power to the plugs), you can measure 24v at the power input to the relay. BUT, no current is flowing. No problem. When the relay is CLOSED (power is flowing to the plugs), the resister drops the voltage to 12 before it hits the relay. Again, no problem.
2. Vehicle with resister bypass: It's all 12v, all the time.

Frankly, that relay could probably handle 48 volts with no problem, anyway.

Go for it!

 

[doghead]

The 12 volt rating for the ST85 relay is for the control coil, not the relay contacts. The relay contacts are rated in amps.

The CUCV control voltage is 12 volts.

Might be worth another run?

No, there have not been any new options.

 

[doghead]

Post #2 is a bit confusing because that info is irrelevant to the relay voltage rating.

There is no voltage rating for the contacts, they are rated in amps.

 

[donalloy1]

Thanks for response Lead Hardchargers! You all rule the MV world.

 

[donalloy1]

I know that my utmost concern is spoken in amperage or load. Voltage levels can be a concern though when motors come into play. I suppose I need not worry with relays...being contacts only?

 

[Skinny]

For the cost and performance, why reinvent the wheel?

Unless you have a GP failure and your system is stock, post #2 makes sense to me.

 

[antennaclimber]

I use these relays for our projects at work. They work well as a GP relay and snow plow relay.

http://www.murcal.com/Catalog/Metal-DC-Contactor-Family/974-1215-011-09

 

[doghead]

For the cost and performance, why reinvent the wheel?

Unless you have a GP failure and your system is stock, post #2 makes sense to me.

In post # 2, he is discussing the facts of the voltages that can be switched(depending on which way your truck is wired).

The fact is, the control(coil) voltage is 12volts. (no matter how your truck is wired)

The switched voltage does not matter(therefore there is no need to discuss the 2 wiring choices).

The OP simply did not understand the fact that the control voltage is 12 volts, and that is why the ST85 relay is rated for 12 volts.

I think anymore discussion will only confuse him(and many others).

 

[donalloy1]

My O9 is OEM! Installing ST85 tomorrow. Looks a little different from previous GPR. Please advise wiring order by color! Thanks DMLII sends respectfully

 

[Warthog]

Large red wire on large terminal.
All orange wires on other large terminal
Small light blue wire on small terminal
Small pink/black wire on other small terminal

Relay should be mounted sideways, not up and down.

 

[MarcusOReallyus]

Looks a little different from previous GPR. Please advise wiring order by color!

Hmmmm. That raises a small yellow flag. Different in what way? The shape or size, or color may be a bit different, but connections should be the same. Can you post a pic of your current setup?

 

[donalloy1]

Hmmmm. That raises a small yellow flag. Different in what way? The shape or size, or color may be a bit different, but connections should be the same. Can you post a pic of your current setup?

MarcusOReallyus, shiny all metal housing vs. plastic. Was pretty sure landings would be same as before. Just wanted make sure! Sorry, I did not take pictures before and after R & R. My only other question is why mount cylinder horizontally vs. vertically as directed on previous post?

 

[MarcusOReallyus]

MarcusOReallyus, shiny all metal housing vs. plastic.

Ah, gotcha.

My only other question is why mount cylinder horizontally vs. vertically as directed on previous post?

Just because that's the way it fits, and the wiring is routed that way. Functionally, you could mount it vertical or even (in theory) upside down.