Union Instruments CWD2000 EX, Original Operating Instructions

Page: 53 / 103

Operation
53
Main menu - Options - I/O - Digital outputs
The digital output can e.g. comprise signals in combination with limit values or
operation messages.
Example:
The Wobbe signal in MJ/m³ has an alarm value at 47,000 and 50,000 MJ. The zero
position is high. The relay for the signals described in the following are switched
under the following conditions:

Process: The solenoid valve for process gas is open and the flame is burning.

Calibrate: The solenoid valve for calibration gas is open and the flame is
burning.

Service: Filter change of air filter (the frequency of the frequency converter is
> 48 Hz) or air inlet temperature > 41°C.

Filter change: Filter change of air filter (The frequency of the frequency
converter is > 48 Hz)

Fault: The air filter is heavily soiled. The differential air pressure is thus < 3.5
mbar

Operation: The flame is burning.

Operation delayed: The flame is burning and the delay time has expired.

Over temperature: The flame is too hot. The Wobbe signal is larger than 76
mV, i.e. the temperature increase in the inner pipe of the thermal battery is
more than 50°C.

Calibration deviation: In a basic calibration you can set a signal which will
trigger and alarm when the deviation to the basic calibration exceeds the
alarm value. This is possible in negative and positive direction.

Int. pressure: An alarm is triggered in case of lack of process gas or lack in
the calibration gas line.