Operation
–
Press the keys (▲+▼) to select the displayed sensor current as the newly
set sensor current. The value is saved and this function is exited. The
display shows CU once again.
–
Press the ▲ key three times to return to measuring mode.
dP – turning the decimal point on
This function is used to select the decimal point in the display if the
DrägerSensor LC M (type XTR 0010 or XTR 0011) or the remote transmitter
type XTR 0090 or XTR 0091 with sensing head SE Ex LC ... DQ is used with a
measuring range of 0 to 9.9 %LEL. The decimal point is only displayed for gas
concentration displays in %LEL.
–
Navigate using the ▲ or ▼ keys until the display shows dP ("decimal Point")
and confirm by pressing the keys (▲+▼). The decimal point is now
displayed if already selected. The flashing point on the bottom right is
switched off.
–
Use the ▲ or ▼ key to turn the decimal point on or off.
–
Press the keys (▲+▼) to save the current status and exit the function. The
display shows dP. The activated decimal point is not displayed, rather the
point at the bottom right flashes once again.
–
Press the ▲ key four three times to return to measuring mode.
So – displaying the software version
To document necessary software modifications, this function can be used to
display the software version implemented in the transmitter.
–
Navigate using the ▲ or ▼ key until the display shows So ("Software") and
confirm by pressing the keys (▲+▼).
–
The display shows a figure between "0.1" and "9.9", indicating the
current software version of the transmitter.
–
Press the (▲+▼) keys to exit the function. The display shows So once
again.
–
Press the ▲ key five three times to return to measuring mode.
4.4
Commissioning the transmitter
–
Open the transmitter's housing cover.
WARNING
Dust explosion protection is not ensured after having opened the transmitter's
housing. The Ex area has to be temporarily de-classified, if necessary!
4.4.1
Turning on the supply voltage
–
After turning on the supply voltage, all 14 LED segments including both
points are activated for approx. 5 seconds to make sure that they are not
faulty ("Lamp test"). Internal test routines run in the transmitter during this
period, the transmitter's output signal is 1 mA.
–
After this, the display changes, with approx. 1 Hz, between two horizontal
lines and the currently measured gas concentration. During this time the
transmitter's output is 3.4 mA.
–
After one minute the transmitter is ready for operation. If the zero-point is
not undercut by more than 5 %LEL or 1 %LEL, it displays the current
measured value, and the output signal corresponds to the measured value.
–
Type XTR 0090 or XTR 0091 with sensing head SE Ex LC M ...DQ: Adjust
the sensor current to 276 mA with the "CU – setting the sensor current"
function (see page 15).
–
Allow the transmitter to warm-up for at least 10 minutes (sensor warm-up
time) before calibration.
4.4.2
Calibrating the transmitter
For this chapter:
Dräger PEX 3000