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Re: voltage stabiliser S3?

PostPosted: Mon Oct 22, 2018 8:36 pm
by billwill
My S3 Elan coupe has alway had a Voltage stabalizer fitted. I am still using the old vibrating type. You can nowadays get electronic type to bring the erratic 12-> 14V down to a stable 10v for the slow thermally operated instruments.


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Re: voltage stabiliser S3?

PostPosted: Tue Oct 23, 2018 6:39 pm
by RogerFrench
pereirac wrote:
alan.barker wrote:Thanks Carl,
So we are only talking about Voltage Stabiliser.
Elan feeds only Fuel Gauge.
Elan plus 2 feeds Fuel Gauge , Temp Gauge.
Alan



Alan, I think the rev counter also relies on the 10 v from the voltage stabiliser. The original stabilisers are not very good and rely on a little thermal switch which opens and closes, a modern semiconductor version would be much better (and probably produce less radio interference)

Carl

(Planning a visit to Brittany again ext year..)


No, the Rev counter is not fed by the stabilizer. At least, it shouldn't be!

Re: voltage stabiliser S3?

PostPosted: Tue Oct 23, 2018 7:45 pm
by alan.barker
Yes the rev counter is 12v supply from ignition with induction loop then to ht coil
Alan

Re: voltage stabiliser S3?

PostPosted: Wed Oct 24, 2018 11:54 am
by The Veg
I can vouch for the solid-state type. I fitted one to my former Esprit and had absolutely no problems with it.

Re: voltage stabiliser S3?

PostPosted: Wed Oct 24, 2018 1:33 pm
by alan.barker
+1 solid state no brainer
Alan

Re: voltage stabiliser S3?

PostPosted: Fri Oct 26, 2018 9:31 pm
by rviani
I am in the process of sorting out instruments for my S3 so appreciate above info.

As I understand it the "early" (S1, S2, early S3) fuel gauge is "FG type" and requires sender with 0 ohm empty and 87 ohm full and runs directly on 12V positive ground ( both may be NLA). Later (late S3, S4) fuel gauge is BF type and requires sender 25ohm full and 250 ohm empty and runs off 10V from voltage stabilizer. Correct?


Similarly early tach is RVI impulse type and runs off 12 volts - later tach is RVC type and requires 10V from stabilizer. Correct?


I happen to have an early tach and late fuel gauge (lucky guy) !


Thanks
Ron

Re: voltage stabiliser S3?

PostPosted: Sat Oct 27, 2018 10:47 am
by Craven
rviani
Your summary is all correct EXCEPT the bit about the RVC tachometer requiring a stabilized supply.
See diagram. All Smiths electronic tachometers have their own simple internal stabilizer by using a Zener Diode allowing them to be connected to the varying battery supply voltage on stabilizer 'B' terminal, ( Battery )
rvi_rvc_tachometer0.jpg and

Re: voltage stabiliser S3?

PostPosted: Tue Oct 30, 2018 8:20 pm
by rviani
Thanks - appreciate the clarification.

Re: voltage stabiliser S3?

PostPosted: Wed Oct 31, 2018 9:44 pm
by toggle45
I have an early 45 S3SE and can confirm it came from factory with no voltage stabilizer fitted. Temp and Oil Pressure gauges were mechanical, and the RVI tach and fuel gauge run off 12-14 volts with no problems. But I switched to an electrical temp gauge, so now need a voltage stabilizer.