DM501A/Repairs

For repair or for building your own temperature sensor you need a PT-100 sensor and a LEMO connector.

The LEMO connector:

• Series: S
• The diameter: 0S (S-Series, diameter 0)
• Insert configuration: 302 (2 pins)

The following LEMO configuration is known to fit:

• Connector: FFA0S302CLA (2.2 to 4.4 mm cable)
• Bend relief: GMA0B035 (3.5 to 3.9 mm cable)

As the PT-100 is connected with only 2 wires, each sensor has to be trimmed with R1001 (offset).

Switch Repair

The contact bar in switches can break. Replacing the contact bar and contacts can be done without desoldering the switches. Refer to the the pictures and the repair section of switch assembly 260-1971-00.

R10 (307-1015-00 input voltage divider) Repair

Fault pattern:  V_DC, V_AC and resistance (exept the lowest range) are 2% to low.

Fault: R10. Some resistors are to low (900 kΩ and 90 kΩ). The "stuff" inside has become liquid. The liquid has a low resistance.

Solution: Open R10. Clean R10 inside with isopropanol and in a ultrasonic bath.

See Also

• Pushbutton switches

Pictures

• 

  Replace the push button plunger and spring contacts on a DM501A

• 

  Defect push button plunger on top and new one below