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Lotus Europa Forums => Garage => Topic started by: Europa73 on Wednesday,January 11, 2017, 07:42:34 PM

Title: Voltage Stabilizer location
Post by: Europa73 on Wednesday,January 11, 2017, 07:42:34 PM
hi all,

I have a 73TCS

Sorry for the simple question.

Where is the Voltage Stabilizer located?

Many thanks,

Title: Re: Voltage Stabilizer location
Post by: BDA on Wednesday,January 11, 2017, 08:11:10 PM
IIRC, the voltage stabilizer is on the back of the dash under the radio on the passenger side. It might also be near the dash rheostat, I'm not sure.   It could be bolted to the fiberglass in front of the dash on the passenger side, but I don't think so.

The parts manual isn't clear (maybe you found that out already!). The closest thing I found to a "voltage stabilizer" was "instrument stabilizer". In the MD section of the parts manual (Electrical Instruments) (see picture below), it shows the instrument stabilizer (#30)in what looks like the bottom area of the dash (that's covered by the console cover). Of course, the picture is not necessarily meant to locate anything. But then in the description block, there are several #30s (see second picture) that are in no way related!

In any event, if you're trying to find it or a place for it, either of those places would be highly likely.

Does that make any sense at all?
Title: Re: Voltage Stabilizer location
Post by: Europa73 on Wednesday,January 11, 2017, 08:34:41 PM
many thanks,
Title: Re: Voltage Stabilizer location
Post by: Grumblebuns on Thursday,January 12, 2017, 08:10:33 AM
BDA is correct, the voltage stabilizer is located behind the dash just to the left of the rheostat looking at the dash. See pic.
Title: Re: Voltage Stabilizer location
Post by: Europa73 on Thursday,January 12, 2017, 05:13:59 PM
Many thanks.

Title: Re: Voltage Stabilizer location
Post by: Argo on Tuesday,January 17, 2017, 03:20:42 AM
The original voltage stabiliser is a very crude electro-mechanical device. You will see what I mean when you open it. It is supposed to maintain an average of about 10 volts. I have replaced it with a solid state 10 volt regulator that should last for ever and be 100% stable as well. See attached.
Title: Re: Voltage Stabilizer location
Post by: BDA on Tuesday,January 17, 2017, 05:52:12 AM
Great way to add lightness!
Title: Re: Voltage Stabilizer location
Post by: Gmg31 on Friday,January 20, 2017, 01:19:14 PM
I'm refitting mine tomorrow and have noticed that the terminals are identical with no markings.  Can anyone advise which is the live feed please
Title: Re: Voltage Stabilizer location
Post by: HealeyBN7 on Saturday,January 21, 2017, 07:26:12 AM
Originally I believe there were three terminals.  Battery, Instrument and Ground.   The middle terminal connects to the instruments (fuel and temp gauge).   

Modern replacements like the one Moss sells, sometimes use the case as the ground, so you will only have two choices:

https://mossmotors.smugmug.com/MossMotors/100000-thru-149999/i-CvF3cXq

You can see a layout of it on page 16 and 18 in my homemade wiring diagram in reply number 4 in the thread below...

http://www.lotuseuropa.org/LotusForum/index.php?topic=1841.msg17352#msg17352

If this doesn't help, maybe post a photo of the back or inside.
Dean
Title: Re: Voltage Stabilizer location
Post by: Grumblebuns on Saturday,January 21, 2017, 08:30:11 AM
If you Google the part number you can get the data sheet. Page 2 has the terminal designations.

http://www.mouser.com/ds/2/389/l78s-974158.pdf

This might be a more compact alternative to the solid state voltage stabilizers offered by the venders.
Title: Re: Voltage Stabilizer location
Post by: jbcollier on Saturday,January 21, 2017, 08:32:12 AM
Yes the case will need to be grounded.  If the terminals are identical and unlabelled then just hook it up and measure the voltage going to the instruments.  If it works, great.  Otherwise just swap the terminals.  It won't hurt it either way.
Title: Re: Voltage Stabilizer location
Post by: 2766R on Sunday,January 22, 2017, 03:57:59 AM
I thought I would add to the thread here.  Found this a while back and plan on this mod on my TC in the future.

http://www.lotus-europa.com/manuals/misc/electrical/vregulator.gif

Of particular interest if going with this mod is note 5. i.e adding a .01ufd cap to prevent oscillation...
Title: Re: Voltage Stabilizer location
Post by: Grumblebuns on Sunday,January 22, 2017, 07:27:59 AM
I built my own voltage stabilizer many years ago, possibly using those instructions. Although it work as designed, I found that trying to fit all of the components in the original box without shorting something out was impossible and left the circuit just hanging behind the dash. Eventually I bought a ready made VS from a vender for $20 to replace my home made VS. You may have better circuit building skills than I did.