"Hot" Relay?

[docc]

Sadly, br(Bruce)lawson passed a few years back. What a kind and gentle soul and all-around good guy. He is missed. 
 

@Weegie, thanks for making the clear distinction between switching and continuous current ratings. Some manufacturers make it difficult to compare ratings “apples to apples.”

[Weegie]

1 hour ago, docc said:

Sadly, br(Bruce)lawson passed a few years back. What a kind and gentle soul and all-around good guy. He is missed. 
 

@Weegie, thanks for making the clear distinction between switching and continuous current ratings. Some manufacturers make it difficult to compare ratings “apples to apples.”

Oh Apologies, I'm sad to hear that @docc

[docc]

All fine. It is good to remember our friends and say their names. 
 

While we have two other relay threads active right now, I felt it was time to bump this one as the heat measurements support the concept that an under rated, poor quality, or otherwise stressed relay is going to be hotter and prone to failure. Plus, these IR temp readers are inexpensive and easy to use.

[Chuck]

Quote

All fine. It is good to remember our friends and say their names. 

Good point, Docc..

[Lucky Phil]

On 10/14/2021 at 4:39 AM, docc said:

All fine. It is good to remember our friends and say their names. 
 

While we have two other relay threads active right now, I felt it was time to bump this one as the heat measurements support the concept that an under rated, poor quality, or otherwise stressed relay is going to be hotter and prone to failure. Plus, these IR temp readers are inexpensive and easy to use.

Of course one solution is to add another dedicated relay for the coils or fuel pump. Should be room.

Ciao  

[docc]

17 minutes ago, Lucky Phil said:

Of course one solution is to add another dedicated relay for the coils or fuel pump. Should be room.

Ciao  

Very interesting comment. I was just looking at High Current relays that are not constrained by the "micro-ISO plug-in" configuration.

Reminds me of abandoning the V11 30amp ATC "Regulator"/charging fuse and hard wiring a robust 30 amp circuit breaker in a "suitable location."

[docc]

Seriously, perhaps the time has come to simply fit a standard size automotive relay for the Fuel pump/Injectors/ coils with a 50 amp rating and forget about it forever . . .

[Lucky Phil]

17 minutes ago, docc said:

Very interesting comment. I was just looking at High Current relays that are not constrained by the "micro-ISO plug-in" configuration.

Reminds me of abandoning the V11 30amp ATC "Regulator"/charging fuse and hard wiring a robust 30 amp circuit breaker in a "suitable location."

Yes docc. I was looking at the RE wiring diagram wondering about their relay load sharing as they use identical units however they only use 4 relays one of which is for accessories. The main difference is the fuel pump relay only does the fuel pump and the main relay supplies the fuel pump power and switch and the ecu. The coils are supplied via the ignition switch and kill switch directly and a fuse. That relieves a relay of the highest load from the coils, some 16 amps. The odd RE's exhibit mystery intermittent shut down for no apparent reason and I was wondering if they suffered from a relay that was loaded to the limit and therefore no headroom but it seems not. Maybe an overloaded ignition switch contact, if the contact is less than pristine from manufacture?

Ciao    

[Lucky Phil]

4 minutes ago, docc said:

Seriously, perhaps the time has come to simply fit a standard size automotive relay for the Fuel pump/Injectors/ coils with a 50 amp rating and forget about it forever . . .

Seems doable  Will the seat still fit? they run close to the base.

 

Ciao

[docc]

1 minute ago, Lucky Phil said:

Seems doable 

 

Ciao

I can almost smell the vapor of rosin core solder . . .

[docc]

8 minutes ago, Lucky Phil said:

Seems doable  Will the seat still fit? they run close to the base.

 

Ciao

The seat base has to be relieved for any changes. I have done this many times: Dremel, cut away the foam, reseal the seat base with RTV silicone or by attaching fitted plates of polyethylene or ABS sheet.