ENMET GSM-60 User Manual

Page 18

GSM-60

ENMET Corporation

5.3 Calibration for CO, O

HC and CO

(Gas Channels)

Calibration is the process of setting the instrument up to read accurately when exposed to a target gas. This is a two step
process. A Low Calibration sets clean air reference point and the High Calibration function sets the sensitivity of the
instrument.

Calibration equipment is available from

ENMET

Corporation to calibrate the

GSM-60

. A list of needed material is in Section

7.0. A calibration adapter will have a fitting for the gas cylinder on one side, and a quick-disconnect to attach to the instrument
on the other.

You may exit the calibration section, at any time, by

pressing and holding the

OPTION

switch for 3 seconds, if entering

calibration section by mistake or calibration gas is not available.

Wait 24 hours after initially supplying air and power to the

GSM-60

sensor before initial calibration. It is not necessary to

open the Front Panel to make adjustment. The calibration functions are operated through the

OPTION

and

SELECT

switches on

the front panel.

After entering a valid password to maintenance menu, see Section 5.2.1, the calibration section is the first menu section; enter
by pressing the

SELECT

switch.

Supply sensor with clean air for LowCal/ZeroCal setting and apply calibration gas for HiCal/SpanGas setting.

Press the

SELECT

switch "

Calibration Select

" is displayed.

= the gas to be calibrated

Press the

OPTION

switch, if needed, to change to the gas to be calibrated.

Press the

SELECT

switch, the gas & current reading are displayed in upper portion of display. The mV reading & "

LowCal

" is displayed in the lower portion of display. This is the LowCal setting,

usually zero, clean air must be supplied to the

sensor. This reading needs to be at or near zero. If it is not then a cylinder of clean 20.9 air should be used. See Figure 7 if
this is required.

Press the

SELECT

switch, that moves the cursor one digit to the right when the last digit is accepted the display will move

to "

HiCal

" gas calibration.

= the level of gas to be used for calibration. The mV reading is shown in the upper right

hand corner of the display.

Apply calibration gas to sensor. See Figure 7. After about 1 minute and mV reading has stabilized.

Press the

SELECT

switch, that moves the cursor one digit to the right, when the last digit is accepted and the calibration is

successful the display will momentarily show Cal OK then slope and off set readings, before returning to the Calibration
Menu

Repeat above steps for each channel to be calibrated.

OTE

Instruments equipped with an oxygen sensor programmed with a range of 0 to 15% by volume require 99.999 % Nitrogen

(

ENMET

Corporation part number 03295-100) be used for the LowCal/ZeroXCal setting and 5% by volume Oxygen

(

ENMET

part number 03296-050) be used for HiCal/Span setting

To continue on too next section Press the

OPTION

switch.

Press

OPTION

switch until “Exit maint menu” appears and then press

SELECT

switch to return the instrument to the

Operational Display

Example: Full Calibration Flow Chart, for CO

From Valid Password Entry

Press

PTION

until the gas to be

Calibrated is displayed

Calibration

Select (Gas)

MAINTENANCE MENU

Calibration

CO:

LowCal: 0000

S each digit

CO:

HiCal: 0000

S each digit

Default Calibration Points

Gas

LowCal HiCal

N/A*

20.9*

CO2

1000

O = Press Option
S = Press Select