Emerson 00809-0100-4514, 1154 manual Check for adequate voltage to the transmitter

Rosemount 1154

Reference Manual

00809-0100-4514, Rev BA January 2008

Symptom	Potential Source	Corrective Action
Low Output or	Primary Element	Check for restrictions at primary element, improper installation or poor condition.
No Output		Note any changes in process fluid properties that may affect output.
	Loop Wiring

		Do not use over 100 volts to check the loop, or damage to the transmitter
		electronics may result.
		Check for adequate voltage to the transmitter.
		Check the milliamp rating of the power supply against the total current being drawn for all
		transmitters being powered.
		Check for shorts and multiple grounds.
		Check for proper polarity at the signal terminal.
		Check loop impedance.
		Check wire insulation to detect possible shorts to ground.
	Impulse Piping	Ensure that the pressure connection is correct.
		Check for leaks or blockage.
		Check for entrapped gas in liquid lines.
		Check for sediment in the transmitter process flange.
		Ensure that blocking valves are fully open and that bypass valves are tightly closed.
		Ensure that density of the fluid in the impulse piping is unchanged.
	Transmitter	Ensure that calibration adjustments are in allowable range.
	Electronics	Check for shorts in sensor leads.
	Connections	Make sure post connectors are clean, and check the sensor connections.
		If the electronics are still suspect, substitute new electronics.
	Test Diode Failure	Replace electronics housing.
	Transmitter	Determine faulty circuit board by trying spare boards. Replace faulty circuit board.
	Electronics Failure
	Sensing Module	NOTE: See Sensing Module Checkout section. The sensing element is not field repairable
		and must be replaced if found to be defective. See “Disassembly Procedure” for instructions
		on disassembly. Check for obvious defects, such as a punctured isolating diaphragm or fill
		fluid loss, and contact Rosemount Nuclear Instruments, Inc. at (952) 949-5210.
	Power Supply	Check the power supply output voltage at the transmitter.
Erratic Output	Loop Wiring

	Do not use over 100 volts to check the loop, or damage to the transmitter
	electronics may result.
	Check for inadequate voltage to the transmitter.
	Check for intermittent shorts, open circuits, or multiple grounds.
Impulse Piping and	Check for entrapped gas in liquid lines, or liquid in dry lines.
Process
Connections
Transmitter	Check for intermittent shorts or open circuits.
Electronics	Make sure that bayonet and sensor connectors are clean and properly connected.
Transmitter	Determine faulty circuit boards by trying spare boards. Replace faulty circuit board.
Electronics Failure
Power Supply	Check power supply output voltage.

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