Scott Safety Protege, User Manual

Page: 63 / 104

Calibrating the Device
39
SCOTT SAFETY 087-0038 REV L
Zero Calibration
This section describes how to perform Zero Calibration.
1
Verify ambient air is free of toxic or combustible gases. If air is not free or cannot
be verified free, obtain a Zero Air gas cylinder.
2
Power on the device.
3
Press and hold the Right Operation Button until PLEASE WAIT displays. It is in
progress. See
Figure 25 .
Figure 25 Zero Calibration Display - In Progress
Warning: To prevent an erroneous Zero Calibration from occurring, the device
displays IS AIR CLEAR? If the device is indicating a gas reading that is 50% or
higher of an alarm set point for any of the gases it is equipped to detect. You have 20
seconds to acknowledge the alert. If the alert is not acknowledged within 20 seconds,
the device powers off. Do not continue with Zero Calibration until air has been
verified free of toxic and combustible gases. Failure to properly perform a zero
calibration may result in injury or death.
Baseline readings for a Zero Calibration are 0 for H
2
S, CO, and LEL, and 20.9% for
O
2
.
Table 11 Recommended Calibration and Test Matrix
ITEM FREQUENCY DETAILS
Zero Calibration
•
Daily
•
When baseline readings are incorrect or
suspect
•
Prior to a Span Calibration
See “Zero
Calibration” on
page 39.
Span Calibration
•
CAL EXPIRED is displayed
•
After installing new sensors
•
When a Bump Test fails
See “Span
Calibration” on
page 40.
Bump Test
•
Daily
•
When a sensor is exposed to a high
concentration of gas
•
When submerged in water
•
When exposed to mechanical shock, such as
being dropped
See “Bump Testing”
on page 43.