Emerson Process Management 1500 manual Checking the core processor LED

Troubleshooting

11.24.1Checking the core processor LED

To check the core processor LED:

1.Maintain power to the transmitter.

2.Remove the core processor lid (see Figure B-2). The core processor is instrinsically safe and can be opened in all environments.

3.Check the core processor LED against the conditions described in Table 11-11 (standard core processor) or Table 11-12 (enhanced core processor).

4.To return to normal operation, replace the lid.

Note: When reassembling the meter components, be sure to grease all O-rings.

Table 11-11Standard core processor LED behavior, meter conditions, and remedies

LED behavior	Condition	Possible remedy
1 flash per second (ON	Normal operation	No action required.
25%, OFF 75%)
1 flash per second (ON	Slug flow	See Section 11.17.
75%, OFF 25%)
Solid ON	Zero or calibration in	If calibration is in progress, no action required. If no calibration is in
	progress	progress, contact Micro Motion. See Section 1.8.
	Core processor	Check power supply to transmitter. See Section 11.14.1, and refer to
	receiving between 11.5 Appendix B for diagrams.
	and 5 volts
3 rapid flashes,	Sensor not recognized	Check wiring between transmitter and sensor (remote core processor
followed by pause		with remote transmitter installation). Refer to Appendix B for diagrams,
		and see your transmitter installation manual.
	Improper configuration	Check sensor characterization parameters. See Section 4.2.
	Broken pin between	Contact Micro Motion. See Section 1.8.
	sensor and core
	processor
4 flashes per second	Fault condition	Check alarm status.
OFF	Core processor	• Verify power supply wiring to core processor. Refer to Appendix B for
	receiving less than 5	diagrams.
	volts	• If transmitter status LED is lit, transmitter is receiving power. Check
		voltage across terminals 1 (VDC+) and 2 (VDC–) in core processor.
		Normal reading is approximately 14 VDC. If reading is normal,
		internal core processor failure is possible. Contact Micro Motion. See
		Section 1.8. If reading is 0, internal transmitter failure is possible.
		Contact Micro Motion. See Section 1.8. If reading is less than 1 VDC,
		verify power supply wiring to core processor. Wires may be switched.
		See Section 11.14.1, and refer to Appendix B for diagrams.
		• If transmitter status LED is not lit, transmitter is not receiving power.
		Check power supply. See Section 11.14.1, and refer to Appendix B
		for diagrams. If power supply is operational, internal transmitter,
		display, or LED failure is possible. Contact Micro Motion. See
		Section 1.8.
	Core processor	Contact Micro Motion. See Section 1.8.
	internal failure

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