Span Adjustment - Emerson MRLDS-450 Installation And Operation Manual

1. Begin zero adjustment:
MRLDS-400 App: On the Home tab select Calibrate then scan the barcode on gas cylinder 
a.
or manually enter values for zero gas.
b. Manual: Hold MAG#1 for more than five (5) seconds. The LED will blink GREEN-GREEN-
RED when the instrument is ready.
2. Apply zero gas (or ambient air per warning above).
3. Confirm the start of calibration:
a. MRLDS-400 App: Press the Start Zero button.
Manual: Tap MAG#1 within 30 seconds or the instrument will time-out and return to normal 
b.
operation.
4. Complete zero adjustment:
a. MRLDS-400 App: App will countdown to completion. If calibration is successful, proceed to
Step 5. If calibration is unsuccessful, return to the Home screen and press the Acknowledge 
button to clear the zero calibration fault.
b. Manual: The LED will blink GREEN-RED, GREEN-RED-RED, GREEN-RED-RED-RED,
etc. until calibration is complete. To abort, hold MAG#1 for >5-seconds, turn off gas flow and
remove the calibration adapter. If calibration is successful (green LED), proceed to Step 5. If 
calibration is unsuccessful (LED blinks orange @ 2 Hz), tap MAG#1 to discard the calibration
attempt.
5. Turn off gas flow from zero gas.
6. Replace zero gas with calibration gas in preparation for span adjustment.

5.2.4. Span Adjustment

IMPORTANT: Except for CO2 or O2 sensors, calibration gas must be in a balance of air,
not nitrogen (N2).
IMPORTANT: At elevations higher than 6,560' (ft) (2,000 m), calibration will result in a
lower reading. Above 6,560' (ft) the instrument should be calibrated in the environment of
operation.
1. Begin span adjustment:
a. MRLDS-400 App: Scan barcode on gas cylinder or manually enter values for zero gas.
b. Manual: Hold MAG#2 for more than five (5) seconds. The LED will blink GREEN-GREEN-
ORANGE when the instrument is ready.
2. Apply calibration gas at the concentration listed on the calibration gas concentration
label (located on top of the instrument).
• Part Number
• Serial Number
• Sensor Type
• Maximum Range
3. Confirm the start of calibration:
Adjustments Care and Maintenance • 29