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Sensor Type:
The user may choose to select the sensor input as a digital or analog. Selecting digital will only allow the
QLC to turn ‘on and off’ a relay when the channel digital input is active. Most applications will utilize an
analog sensor.
When all programming is complete, use ‘EXIT’ and ‘ENTER’ to return to the ‘MAIN’ screens.
MAINTENANCE AND TROUBLE SHOOTING
MAINTENANCE:
The Myriad QLC is a digital solid state device which requires no periodic maintenance.
Occasional physical checks of the unit should be carried out for physical and mechanical security of
mounting, terminal blocks, and electrical wiring.
TROUBLE SHOOTING:
UNIT ‘LOCKS UP’ – Recycle power to the unit by removing AC power, waiting 10 seconds and
reconnecting power.
.
LCD display goes dim or contrast is poor. Remove power from the unit, release the 2 rear mounting
screws and slide the unit forward in its case approximately 1 inch. On the left side of the circuit
board is an adjustable potentiometer. With a small screwdriver adjust this “pot” to allow alter the
contrast to the desired amount. Return the unit to its normal position and secure the rear screws.
DISPLAY REMAINS AT ZERO OR SHOWS NO CHANGE -- If the display remains at zero or
shows no change but the process is changing, check for D.C. voltage on the loop. With 2 wire
(4/20MA) instruments check with a D.C. voltmeter at the level instrument, by disconnecting the level
instrument from its terminals ( AI1, AIC) and measuring across these terminals with a D.C. voltmeter
for the presence of 24VDC.
NOTE: This should be done by using the user provided circuit breaker or fuse,
not by removing the power wires at the terminal block. Serious injury or death
can occur if contact is made with the incoming ac power.
WARNING
Summary of Contents for MYRIAD QLC
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