Quote:
Originally Posted by sparkymike
I am also wondering if the movement magnets have lost a bit of power.
This might cause meter needle to swing more than it should. Is that possible ?
I will change the rectifier out first before I try another movement.
Mike.
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It depends on what you mean by swing.
If you mean that the pointer oscillates more than normal before settling to the final value (reduced damping), it is very likely that the chain of resistors that should be shunting the movement is open circuit. The possible fault could either be an open circuit resistor or a switching fault. This would also give a high than correct deflection.
If you mean that the deflection of the pointer is less than normal, one possible cause could be loss of magnet flux. These meters have a magnetic shunt which can be adjusted to give the correct value of deflection, but only a range of a few percent.
PMM