Applies To: 2590
Problem Description: Standby current on the 2590 is excessive.
Resolution/Work Around:
The 2590 should source 10 uA if the 1594A/1595A is set up with Standby Current on and the Sensing Current is set to 0.01 mA and if the sensor resistance is higher than about 620 ohms. If the sensor resistance is less than 620 ohms (the typical range of PRT resistance) the 2590 can only apply 1 mA or 0.5 mA (even if the 1594A/1595A Sensing Current is set to 10 uA).
There should not be any condition that would cause the standby current to be 25 uA, or 800 uA. If that is the case, the 2590 should be returned to an authorized Fluke Service Center for repair.