12v rpm gauge on 24v ?

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jan.bauwmans
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12v rpm gauge on 24v ?

Post by jan.bauwmans »

Hi,

Can I use a VDO 12V RPM gauge on the 24V circuit of the Pinz ?

Rgds

Jan

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rmel
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Re: 12v rpm gauge on 24v ?

Post by rmel »

I have several VDO catalogs, instruments are listed as either 12V or 24V but there are fewer 24V options.
Their gauges are either 12V or 24V they do not support gauges that support both 12V or 24V.

If you have a 12V tach and just want to use it, I'd recommend getting on Amazon or eBay and search
for a mini 24V to 12V DCDC converter. There are many choices out there. Read the feedback carefully,
there is also a lot of junk out there.

If your shopping for a tach, you may find a brand out there that does support a wide input voltage range.
Puller: 71' 710K 2.7L EFI aka Mozo
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ChickenPinz
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Re: 12v rpm gauge on 24v ?

Post by ChickenPinz »

I can't speak for the VDO gauges, but I wanted to add that some sold-as-12V gauges may be just fine in a 24V system.

I had an old Sun Super Tach II of similar vintage to the Pinz, and reverse-engineering the circuit made it clear that 24V operation was fine, and it works well in the Pinz.

YMMV.
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Stumbler
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Re: 12v rpm gauge on 24v ?

Post by Stumbler »

If you have already purchased the gauge and cannot return it for a 24V version, there are quite a few small DC-DC converters that are about the size of a pen or a large pack of matches. They only cost a few dollars. I have a couple backup marker lights that I could only find in 12V LED form and I put transformers on them. They've been working perfectly for years.
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