Solid State DME Relay being developed
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From: CA>Oklahoma!
Mine arrived today, the "pump prime" version. This appears to be a top quality unit, and the modern electronics should be much more dependable than the dodgy old relays. Great to have one of the niggling issues with our 993 now fully sorted.
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From: Bend, OR
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From: Vancouver, BC
I am a bit confused. Is "Pump prime" allowing the fuel pimp to build pressure before starting? Did a switch get put in so we can crank the car to circulate/build oil pressure without ignition or fuel pump activation? That is a key feature for me, having to wait a few seconds every start for fuel pressure would be a total irritant.
Cheers
Mike
Cheers
Mike
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From: Oregon
Maybe we're (as discussed with a friend) missing something here...
And certainly not to poo-poo any new idea; but the failure mode associated with the DME relay as it currently stands, are the solder joints, yes?
So as Steve Weiner has mentioned time and time again, if you reflow the existing joints of the relay, one should have a very dependable relay.
Chips in solid state components have solder joints too, ya know! And certain chips can also be Electro-Static Discharge (ESD) sensitive as well.
As others have asked, to what solder specification are these SS DME relays soldered to, ASME, ANSI, and to whatever specific solder spec is employed; does it meet or exceed current automotive specifications?
Just some thoughts to toss out to the crowd...I would recommend everyone interested, read the FULL thread on Pelican, prior to purchase.
And certainly not to poo-poo any new idea; but the failure mode associated with the DME relay as it currently stands, are the solder joints, yes?
So as Steve Weiner has mentioned time and time again, if you reflow the existing joints of the relay, one should have a very dependable relay.
Chips in solid state components have solder joints too, ya know! And certain chips can also be Electro-Static Discharge (ESD) sensitive as well.
As others have asked, to what solder specification are these SS DME relays soldered to, ASME, ANSI, and to whatever specific solder spec is employed; does it meet or exceed current automotive specifications?
Just some thoughts to toss out to the crowd...I would recommend everyone interested, read the FULL thread on Pelican, prior to purchase.
Last edited by nine9six; Jan 6, 2016 at 09:11 PM.
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From: Colorado
I would assume that he addressed the single greatest cause of failure with these new relays, i.e. solder, in his design.
There is extremely little concern for ESD in a solid state switch, of which I would say this device by design would be immune. Are you considering EMI as well? Yes, it's just as ridiculous.
Are you expecting him to design to a MIL-STD-38534 or in a QML foundry? Give me a break. The guy found a need, designed what appears to be a professional product, and brought it to market. If you don't like it, don't buy one but don't act like it needs to meet NASA standards.
There is extremely little concern for ESD in a solid state switch, of which I would say this device by design would be immune. Are you considering EMI as well? Yes, it's just as ridiculous.
Are you expecting him to design to a MIL-STD-38534 or in a QML foundry? Give me a break. The guy found a need, designed what appears to be a professional product, and brought it to market. If you don't like it, don't buy one but don't act like it needs to meet NASA standards.
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From: Canada & the Alps
The old relays aren't taxed electrically. The contacts on mine were fine both physically and electrically...the latter while I had the maximum current going through them and measuring the voltage drop across them was in the millivolts.
I bet my old relay that I desoldered and resoldered will outlast the car.
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From: Oregon
I would assume that he addressed the single greatest cause of failure with these new relays, i.e. solder, in his design.
There is extremely little concern for ESD in a solid state switch, of which I would say this device by design would be immune. Are you considering EMI as well? Yes, it's just as ridiculous.
Are you expecting him to design to a MIL-STD-38534 or in a QML foundry? Give me a break. The guy found a need, designed what appears to be a professional product, and brought it to market. If you don't like it, don't buy one but don't act like it needs to meet NASA standards.
There is extremely little concern for ESD in a solid state switch, of which I would say this device by design would be immune. Are you considering EMI as well? Yes, it's just as ridiculous.
Are you expecting him to design to a MIL-STD-38534 or in a QML foundry? Give me a break. The guy found a need, designed what appears to be a professional product, and brought it to market. If you don't like it, don't buy one but don't act like it needs to meet NASA standards.
After that, the rest of your tangent and senseless references to EMI, MIL-STDs, NASA standards, and QML foundry, which are currently flooded with substandard knock-off Chinese microchips, were nothing more than...nothing!
At least my references to ANSI and ASME standards are real and used throughout commercial and automotive practices.
Time, design robustness, and propper mgt. will dictate the success or failure of the SSR's.
Personally speaking, I hope the designer has a home run on his hands!
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From: Colorado
Originally Posted by nine9six
Your first mistake and where you lost me..."I would assume..."
After that, the rest of your tangent and senseless references to EMI, MIL-STDs, NASA standards, and QML foundry, which are currently flooded with substandard knock-off Chinese microchips, were nothing more than...nothing!
At least my references to ANSI and ASME standards are real and used throughout commercial and automotive practices.
Time, design robustness, and propper mgt. will dictate the success or failure of the SSR's.
Personally speaking, I hope the designer has a home run on his hands!
After that, the rest of your tangent and senseless references to EMI, MIL-STDs, NASA standards, and QML foundry, which are currently flooded with substandard knock-off Chinese microchips, were nothing more than...nothing!
At least my references to ANSI and ASME standards are real and used throughout commercial and automotive practices.
Time, design robustness, and propper mgt. will dictate the success or failure of the SSR's.
Personally speaking, I hope the designer has a home run on his hands!
However, the very fact that you mentioned QML and Chinese in the same sentence tells me you lack even a basic understanding of procurement and design standards. I'm done flooding this guys thread with tangential arguments. I've already ordered mine and can't wait to get it. The fact that you brought up ESD concerns on a simple solid state switch puts your entire statements credibility in the garbage and shows that you background isn't in electrical engineering. Have a great day!
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Michael S. Palmer
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From: Canada & the Alps
Having read the OPs Blog, sure, solder joints are not the only mode of failure of our OEM relays, but they are certainly the only mode I have read about here and of the ones I've repaired both my own and those of a few members.
But the blog makes it sound like a SSR can never fail and they can and do.
By the way, how about some technical specs.
With respect to the voltage at pin 30, what are the guaranteed minimum voltages at pins 87 and 87b. On my OEM relay, they are equal, but there are always drops across electrical switches (I am assuming FETs are used)?
But the blog makes it sound like a SSR can never fail and they can and do.
By the way, how about some technical specs.
With respect to the voltage at pin 30, what are the guaranteed minimum voltages at pins 87 and 87b. On my OEM relay, they are equal, but there are always drops across electrical switches (I am assuming FETs are used)?
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From: Plano, Texas
I thought the oem mechanical relay also allows the prime pump feature,no? It's only if you turn the key to 'on' you hear the pump run. If you pass thru 'on' and go directly to 'start' there is no delay in starting it just all happens at the same time. I read it that the prime pump SS version would run this way like the oem. NOT that you turn to 'start' and have a mandatory 3 second wait. Perhaps the op can clear that up.
Best of luck with the product!
Best of luck with the product!
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Technically Solid-State Relay is wonderful, but this is my concern:
- If this SSR follows RoHS (non-Lead) requirement then: Don't expect solder stays intact for more than 10 years.
- Surface Mount is less vibration proof than through hole.
- The board surface doesn't cover/ mask by non-conducted rubber material (damping vibration).
Regards,
Tuan-
- If this SSR follows RoHS (non-Lead) requirement then: Don't expect solder stays intact for more than 10 years.
- Surface Mount is less vibration proof than through hole.
- The board surface doesn't cover/ mask by non-conducted rubber material (damping vibration).
Regards,
Tuan-
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From: Oregon
Without quoting additional senseless references; I submit the following...
practices employed in the procurement and management of electronic parts ..... Counterfeit versions of components on the QML and Qualified Products List .... The majority of counterfeit parts are being discovered because they are returned as...
...Not that anyone would care to read more...
https://www.google.com/url?sa=t&sour...cQ9tCsHaChZgRw
I now return you back to your regular scheduled 993 forum reading...
practices employed in the procurement and management of electronic parts ..... Counterfeit versions of components on the QML and Qualified Products List .... The majority of counterfeit parts are being discovered because they are returned as...
...Not that anyone would care to read more...
https://www.google.com/url?sa=t&sour...cQ9tCsHaChZgRw
I now return you back to your regular scheduled 993 forum reading...
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From: Colorado
Originally Posted by Quadcammer
You can't wait to get a relay?????
Must be a slow day at the 71-3.0-911 household
Must be a slow day at the 71-3.0-911 household
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From: Del Mar
I thought the oem mechanical relay also allows the prime pump feature,no? It's only if you turn the key to 'on' you hear the pump run. If you pass thru 'on' and go directly to 'start' there is no delay in starting it just all happens at the same time. I read it that the prime pump SS version would run this way like the oem. NOT that you turn to 'start' and have a mandatory 3 second wait. Perhaps the op can clear that up.
Best of luck with the product!
Best of luck with the product!
Also wondering about this. Can anyone who has received the pump-prime version answer this?
