cerm78

Hi everybody!

I have an Invision S7 oil pressure gauge that I bought some time ago. I have installed the sender unit in a car I had but it was damaged and it's not working anymore. So I have the almost new oil pressure gauge but I don't have a working sending unit.

I have written to AC Autotechnics several times and I have had no answer from them.

Now I'm looking for a compatible sending unit from another brand, but I don't know for what output voltage to look at.

Does somebody know if there are replacement sending units for AC Autotechnic gauges? Is Autometer full sweep sending unit compatible with the Invision S7 gauge?

Thanks in advance!

Esteban

cerm78

I did my homework and tested the gauges against a variable pod resistor. Didn't have too much time so I only did a three point mapping of the resistance against the values shown by the needle.

For oil pressure I have that:
- Minimum Oil Pressure 0 PSI = 0-10 ohm
- Halfway Oil Pressure 50 PSI = 40-50 ohm
- Maximum Oil Pressure 100 PSI = 90-100 ohm

So it seems that oil pressure sensor range is from 0 to 100 Ohm and has an almost linear response.

On the other hand, for water temperature I have that:
- Minimum Temp 105 deg F = 90-100 ohm
- Halfway Temp 202 deg F = 10-15 ohm
- Maximum Temp 300 deg = 0-5 ohm

So it seems that temperature sensor range is from 0 to 100 Ohm, like the oil pressure sender, but it has a exponential response and it is inversely proportional to the temperature.

Now I'll have to search for senders that have the same or similar behavior, but if I don't get accurate readings, I think I won't need them, as all my cluster gauges work fine.


Thanks again!