DOD PS-7 operation manual Changing Settings, 2-1Span Adjustment

2 Changing Settings

2-1 Span Adjustment

Toxic gas sensor unit : CDS-7

Combustible gas sensor unit : CHS-7

(1) Set to maintenance mode (MNT1 or MNT2).

TROUBLE lamp (yellow) blinks.

The “__” indication and the concentration value of the detected gas blink alternately.

MNT1 or MNT2 is displayed at the bottom of the LCD screen.

Left: Maintenance 1 (MNT1)

Center: Normal mode

Right: Maintenance 2 (MNT2)

Pull back to open

(2) Release the password lock. (Refer to 1-2 Releasing the Password Lock.)

(3) Press the SPAN switch.

SPAN switch

(4) Let the calibration gas through.

SPAN is displayed at the bottom right of the LCD screen.

(5)Use the UP/DOWN switch to adjust the concentration indication on the screen to that of the calibration gas concentration.

(6) Once adjustments have been done, press the SPAN

switch again. The SPAN indication in the bottom right of the LCD screen will go off, and the span adjustment will be completed.

UP/DOWN switch

(7)Remove the calibration gas, check that the detected gas concentration is under that of the alarm value, and restore to the normal mode (by switching the maintenance switch to the center).