3 calibration for co, o, Hc and co, Gas channels) – ENMET MEDAIR 2200 User Manual

Page 18

2200

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

2200

. 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

2200

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 XX

" 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 0

" 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 xx

" 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.
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

OTE

The dew point sensor/probe can not be calibrated in the field and should be replaced every two years.

Calibration

Select (Gas)

MAINTENANCE MENU

Calibration

Press

PTION

until the gas to be

Calibrated is displayed

CO: XX

LowCal: 0000

S each digit

CO: XX

HiCal: 0000

S each digit

Default Calibration Points

Gas

LowCal HiCal

N/A

20.9

1000

O = Press Option
S = Press Select