Emerson Process Management 1500 manual 11.25.2 4-wire remote installation, Possible cause Solution

Troubleshooting

Table 11-14Sensor and cable short to case possible causes and remedies

Possible cause	Solution
Moisture inside the sensor junction box	Make sure that the junction box is dry and no corrosion is present.
Liquid or moisture inside the sensor case	Contact Micro Motion. See Section 1.8.
Internally shorted feedthrough (sealed passage	Contact Micro Motion. See Section 1.8.
for wiring from sensor to sensor junction box)
Faulty cable	Replace cable.
Improper wire termination	Verify wire terminations inside sensor junction box. See Micro
	Motion’s 9-Wire Flowmeter Cable Preparation and Installation Guide
	or the sensor documentation.

11.25.24-wire remote installation

If you have a 4-wire remote installation (see Figure B-1):

1.Power down the transmitter.

2.Remove the core processor lid.

Note: You may disconnect the 4-wire cable between the core processor and the transmitter, or leave it connected.

3.If you have a standard core processor – Loosen the captive screw (2.5 mm) in the center of the core processor. Carefully remove the core processor from the sensor by grasping it and lifting it straight up. Do not twist or rotate the core processor.

4.If you have an enhanced core processor – Loosen the two captive screws (2.5 mm) that hold the core processor in the housing. Gently lift the core processor out of the housing, then disconnect the sensor cable from the feedthrough pins. Do not damage the feedthrough pins.

CAUTION

If the core processor (feedthrough) pins are bent, broken, or damaged in any way, the core processor will not operate.

To avoid damage to the core processor (feedthrough) pins:

•Do not twist or rotate the core processor when lifting it.

•When replacing the core processor (or sensor cable) on the pins, be sure to align the guide pins and mount the core processor (or sensor cable) carefully.

5.Using a digital multimeter (DMM), check the pickoff coil resistances by placing the DMM leads on the pin pairs. Refer to Figure 11-2 (standard core processor) or Figure 11-3 (enhanced core processor) to identify the pins and pin pairs. Record the values.

112 Micro Motion® Model 1500 Transmitters with the Filling and Dosing Application