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Discussion Starter · #1 ·
Having temp gauge issues, gauge reads to hot (by 40 degrees) compared to thermometer. The gauge manufacturer admits there are problems with the sensors compatability and some aluminum (mine) intakes. He has suggested placing a 40 ohm 1 watt resistor in line between sender and gauge. I couldn't find a resistor of that size so I placed two 22 ohm 1/2 watt resistors in line. Now the gauge dosn't work at all?????? (Haneline Gauges and ProComp intake) Any suggestions???
 

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You were close to put two 22 ohm R's in series, achieving 44 vs. 40 ohms, but if the spec calls for 1 watt components you need them to be able to handle that much power or they will go bad and their resistance will change significantly.

Re-test them to see if they are still ~22 ohms each, or better yet, 44 ohms in series (while out of the rest of the circuit), and if so, that's not the problem.

If they don't, back to Radio Shack for some 1 watt parts.

Brian
 

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Discussion Starter · #3 ·
Hey Austin, someone told me that using them in series (in line) that they multiply values at the rate of each value (22x22) and if I had used them in parallel they would double in value achieving my desired application, any thoughts on that???
 

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Originally posted by Wantdat:
Hey Austin, someone told me that using them in series (in line) that they multiply values at the rate of each value (22x22) and if I had used them in parallel they would double in value achieving my desired application, any thoughts on that???
They told you wrong. In series, you ADD the resistance. In parallel, if my memory serves, you add the reciprocal of each.

Is it the RANGE that's off? In other words, is the gauge off by 40 degrees at each point? Or is the slope off? Meaning it might be perfect at one temp and off by 40 at another point?

If it's purely the RANGE, the resistor will work. You just need the right one.

d



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Discussion Starter · #5 ·
Thanks Naga, Guage is reading 230 and temp appears to be maxing around 188 at highest reading according to the infrared t-mometer..
 

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Discussion Starter · #6 ·
Any other opinions???
 

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1/2 watt is correct. 2 22 Ohm 1/2W resistors in series is the same as one 44 Ohm 1 watt resistor.

What is the sender? Is is an thermal resistor, thermocouple, or diode?

Mike
 

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If you have a sender that has grounding issues, solder a ground wire to a small hose clamp. Place the hose clamp around the sender and attach the other end of the wire to a good ground, engine block, etc.
 

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Originally posted by NAGA:
</font><blockquote>quote:</font><hr />Originally posted by Wantdat:
Hey Austin, someone told me that using them in series (in line) that they multiply values at the rate of each value (22x22) and if I had used them in parallel they would double in value achieving my desired application, any thoughts on that???
They told you wrong. In series, you ADD the resistance. In parallel, if my memory serves, you add the reciprocal of each.


d
</font>[/QUOTE]Onemore step with parallel circuits; you then find the reciprocal of your answerIE:

2- 4 ohm in parallel equals 1/4 + 1/4=1/2
the reciprocal of 1/2= 2
 
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