Notices
928 Forum 1978-1995
Sponsored by:
Sponsored by: 928 Specialists

Relay question...OE -vs- Solid State

Thread Tools
 
Search this Thread
 
Old Dec 9, 2021 | 03:18 PM
  #1  
Speedtoys's Avatar
Speedtoys
Thread Starter
Addict
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 13,583
Likes: 1,046
From: Boulder Creek, CA
Default Relay question...OE -vs- Solid State

What are the disadvantages of a solid state relay in place of the three critical 53B's?

Yes, other than the price. Because a relay not working on it's own is priceless.

Amazon Amazon
Reply
Old Dec 9, 2021 | 03:30 PM
  #2  
Zirconocene's Avatar
Zirconocene
Rennlist Member
5 Year Member
 
Joined: Feb 2019
Posts: 3,539
Likes: 1,013
From: PDX Adjacent
Default

OMG, it's like you're living in my head right now. I have been reading about these things since yesterday and very interested to read what people respond with.

If it's possible, it really seems like the fuel pump relay would benefit the most from this, but maybe there are others that are as, or more critical. I just know that pulling that particular relay on my S4 sucks for access.

ETA: While the Hellas that you linked to at Amazon are relatively common, Wurth Electronik also makes a 5 pin solid state version, with the 87 and 87a terminals, in various amp ratings and NO and NC flavors. However, I have not been able to find a vendor online that offers the Wurth products.

Cheers

Last edited by Zirconocene; Dec 9, 2021 at 03:32 PM.
Reply
Old Dec 9, 2021 | 03:30 PM
  #3  
icsamerica's Avatar
icsamerica
Burning Brakes
5 Year Member
 
Joined: Mar 2018
Posts: 915
Likes: 373
Default

Found this review for the Hella SSR on the jungle website. My take, if you're burning through traditional relays something else is wrong with the system, too much load, etc. I've got about 10 cars I care for and I seldom replace a relay, it happens but it's rare. I also like the audible click that can aide with diagnostics.

Reply
Old Dec 9, 2021 | 03:36 PM
  #4  
Zirconocene's Avatar
Zirconocene
Rennlist Member
5 Year Member
 
Joined: Feb 2019
Posts: 3,539
Likes: 1,013
From: PDX Adjacent
Default

@icsamerica : This article (https://dsportmag.com/the-tech/educa...motive-relays/) seems to indicate that proper wiring might help to mitigate adoption of these relays. Of course, it seems like it would not then be backward compatible with the electromechanical types.

Maybe/hopefully someone like @Alan can chime in. I don't even play an EE on TV.

Cheers
Reply
Old Dec 9, 2021 | 04:11 PM
  #5  
Speedtoys's Avatar
Speedtoys
Thread Starter
Addict
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 13,583
Likes: 1,046
From: Boulder Creek, CA
Default

Originally Posted by icsamerica
Found this review for the Hella SSR on the jungle website. My take, if you're burning through traditional relays something else is wrong with the system, too much load, etc. I've got about 10 cars I care for and I seldom replace a relay, it happens but it's rare. I also like the audible click that can aide with diagnostics.
That doesnt make sense..it -is- the same 1A configuration...and has plenty of trigger current to it...
Reply
Old Dec 9, 2021 | 04:51 PM
  #6  
FredR's Avatar
FredR
Rennlist Member
20 Year Member
 
Joined: Jun 2005
Posts: 10,579
Likes: 1,030
From: Oman
Default

There is nothing wrong with SSL- that is the way the process industries went some 25 years ago when relay logic more or less went defunct overnight due to the added reliability SSL has when protecting millions of dollars worth of assets. That being said the stock relays are reliable and cheap as chips so why bother? I rate them for 20 years of service then replace them for the operationally critical ones at least.
Reply
Old Dec 9, 2021 | 08:23 PM
  #7  
Michael Benno's Avatar
Michael Benno
Rennlist Member
10 Year Member
 
Joined: Mar 2015
Posts: 2,678
Likes: 1,330
From: Portland, OR
Default

Originally Posted by Zirconocene
OMG, it's like you're living in my head right now. I have been reading about these things since yesterday and very interested to read what people respond with.

If it's possible, it really seems like the fuel pump relay would benefit the most from this, but maybe there are others that are as, or more critical. I just know that pulling that particular relay on my S4 sucks for access.

ETA: While the Hellas that you linked to at Amazon are relatively common, Wurth Electronik also makes a 5 pin solid state version, with the 87 and 87a terminals, in various amp ratings and NO and NC flavors. However, I have not been able to find a vendor online that offers the Wurth products.

Cheers
Now you are in my head. I was thinking the same thing. Solid state relays seem the way to go. Would you mind sharing posts of the relays you found?

The one question I have is about amp ratings. While the '53" relays all use a 40amp rating relay the stuff they switch are far lower than 40amp. would it be wise to use a relay amp rating that matched the fuse rating on the circuit?
Reply
Old Dec 9, 2021 | 08:50 PM
  #8  
Speedtoys's Avatar
Speedtoys
Thread Starter
Addict
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 13,583
Likes: 1,046
From: Boulder Creek, CA
Default

Originally Posted by Michael Benno
Now you are in my head. I was thinking the same thing. Solid state relays seem the way to go. Would you mind sharing posts of the relays you found?

The one question I have is about amp ratings. While the '53" relays all use a 40amp rating relay the stuff they switch are far lower than 40amp. would it be wise to use a relay amp rating that matched the fuse rating on the circuit?
That might be more rush current, but the SS ones can do large rush currents as well.

Reply
Rennlist Stories

The Best Porsche Posts for Porsche Enthusiasts

story-0

Talos Takes Your 991 Porsche 911 GT3 to the Next Level for a Cool $1.13 Million

 Verdad Gallardo
story-1

9 Vehicles Porsche Helped Engineer that Aren't Porsches

 Verdad Gallardo
story-2

9 Features and Characteristics That Only Porsche People Understand

 Verdad Gallardo
story-3

I've Written 500 Rennlist Articles: Here's How Porsche Has Changed Along the Way

 Joe Kucinski
story-4

10 Most Unnecessary Porsches Ever Built (And Why We Love Them)

 Verdad Gallardo
story-5

Porsche 911 GT3 S/C vs 718 Spyder RS: 10 Categories, One Winner

 Joe Kucinski
story-6

This Builder Is Turning Heads With Its Slantnose 911 Creation

 Verdad Gallardo
story-7

Porsche 911 GT3 Artisan Edition Pays Homage to Japanese Culture

 Verdad Gallardo
story-8

Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look

 Verdad Gallardo
story-9

10 Porsche Colors That Have More Personality Than Most People

 Verdad Gallardo
Old Dec 9, 2021 | 10:07 PM
  #9  
Zirconocene's Avatar
Zirconocene
Rennlist Member
5 Year Member
 
Joined: Feb 2019
Posts: 3,539
Likes: 1,013
From: PDX Adjacent
Default

Hi Michael-

Here is the link to the Wurth products: https://www.we-online.com/web/en/int..._reference.php, with lots of pretty good detail.

Here is the Hella product page, with a lot less detail: https://www.hella.com/microsite-elec...relay-130.html

Cheers

Reply
Old Dec 9, 2021 | 11:02 PM
  #10  
karl ruiter's Avatar
karl ruiter
Rennlist Member
20 Year Member
 
Joined: Jan 2003
Posts: 3,426
Likes: 223
From: Honolulu and sometimes L.A.
Default

The advantage of SS relays is that they fix the primary problem with mechanical ones, which is that they arc a little bit when they open and close, which damages the contacts leading to degradation over time.
Reply
Old Dec 9, 2021 | 11:53 PM
  #11  
huskeric's Avatar
huskeric
Banned
 
Joined: Nov 2012
Posts: 933
Likes: 264
From: Oak Creek WI
Default

Been running a solid state DME relay in my 89 951 for some time and is not fickle like the OEM relay.
Reply
Old Dec 10, 2021 | 12:20 AM
  #12  
Michael Benno's Avatar
Michael Benno
Rennlist Member
10 Year Member
 
Joined: Mar 2015
Posts: 2,678
Likes: 1,330
From: Portland, OR
Default

Originally Posted by huskeric
Been running a solid state DME relay in my 89 951 for some time and is not fickle like the OEM relay.
can you post a link to the unit you are using!
Reply
Old Dec 10, 2021 | 08:07 AM
  #13  
Zirconocene's Avatar
Zirconocene
Rennlist Member
5 Year Member
 
Joined: Feb 2019
Posts: 3,539
Likes: 1,013
From: PDX Adjacent
Default

Here you go, Michael: https://www.ftech9.com/new-products?...tate+Relays%29

Cheers
Reply
Old Dec 10, 2021 | 08:22 AM
  #14  
Bulvot's Avatar
Bulvot
Three Wheelin'
15 Year Member
 
Joined: Dec 2008
Posts: 1,309
Likes: 559
Default

....

Last edited by Bulvot; Dec 10, 2021 at 07:06 PM.
Reply
Old Dec 10, 2021 | 08:51 AM
  #15  
Bulvot's Avatar
Bulvot
Three Wheelin'
15 Year Member
 
Joined: Dec 2008
Posts: 1,309
Likes: 559
Default

...

Last edited by Bulvot; Dec 10, 2021 at 07:06 PM.
Reply



All times are GMT -3. The time now is 07:30 PM.

story-0
Talos Takes Your 991 Porsche 911 GT3 to the Next Level for a Cool $1.13 Million

Slideshow: Talos Vehicles has transformed the Porsche 911 GT3 RS into a carbon-bodied, race-inspired machine that costs well over $1 million before the donor car is even included.

By Verdad Gallardo | 2026-05-19 13:39:04


VIEW MORE
story-1
9 Vehicles Porsche Helped Engineer that Aren't Porsches

Slideshow: Long before engineering consulting became trendy, Porsche was quietly helping other automakers build everything from supercars to economy hatchbacks.

By Verdad Gallardo | 2026-05-15 12:44:44


VIEW MORE
story-2
9 Features and Characteristics That Only Porsche People Understand

Slideshow: Some brands build cars. Porsche builds traditions, obsessions, and a few habits that stopped making sense decades ago but somehow became part of the charm.

By Verdad Gallardo | 2026-05-13 18:46:13


VIEW MORE
story-3
I've Written 500 Rennlist Articles: Here's How Porsche Has Changed Along the Way

Slideshow: Six years and 500 Rennlist articles later, these are the biggest changes at Porsche.

By Joe Kucinski | 2026-05-11 09:52:55


VIEW MORE
story-4
10 Most Unnecessary Porsches Ever Built (And Why We Love Them)

Slideshow: Some Porsches exist for very specific reasons-others feel like they were built just to see if anyone would notice.

By Verdad Gallardo | 2026-05-06 18:00:32


VIEW MORE
story-5
Porsche 911 GT3 S/C vs 718 Spyder RS: 10 Categories, One Winner

Slideshow: Choosing between the 911 GT3 S/C and 718 Spyder RS in 10 key categories to determine one surprising winner.

By Joe Kucinski | 2026-05-05 12:51:46


VIEW MORE
story-6
This Builder Is Turning Heads With Its Slantnose 911 Creation

Slideshow: A small Polish tuner has reimagined the Porsche 911 Slantnose for the modern era, blending 1980s nostalgia with widebody tuning culture and serious performance upgrades.

By Verdad Gallardo | 2026-05-01 10:49:43


VIEW MORE
story-7
Porsche 911 GT3 Artisan Edition Pays Homage to Japanese Culture

Slideshow: Porsche has created a Japan-only 911 GT3 Artisan Edition that blends track-ready hardware with design cues inspired by traditional Japanese craftsmanship.

By Verdad Gallardo | 2026-04-28 19:37:40


VIEW MORE
story-8
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look

Slideshow: Porsche's latest electric Cayenne Coupe blends dramatic styling with supercar acceleration, turning the brand's midsize SUV into a 1,139-horsepower flagship.

By Verdad Gallardo | 2026-04-27 19:39:30


VIEW MORE
story-9
10 Porsche Colors That Have More Personality Than Most People

Slideshow: Porsche's wildest paint colors aren't just shades-they're full-blown personalities on four wheels.

By Verdad Gallardo | 2026-04-27 19:38:13


VIEW MORE