M&C SP Series, Instruction Manual

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www.mc-techgroup.com SP2000, SP2300, SP2400 | 1.00.03 37
16.4.1.3 Function and adjustment of the time delay relay K1
After the back purge action, the time relay K1 (EZ12AV) finishes the message „Back purge“ with
a time delay of eg. 1 min and releases the measurement again in order to have sample gas in
the analyzers when you switch over from back purging to measuring.
In the front of the time relay, the switches for the time basis T and the multiplicator xT are
situated.
Example:
Delay time: 1 min.
Adjust the time basis T to 1 min. and the multiplicator xT to 1 (1 x 1 min. = 1 min).
16.4.1.4 Function for ball valve position NC „normally closed“
After actuation of the back purge action by K3 (type CT-MXS.22), the message purging is given via the time relay
K1 (EZ12AV), the control solenoid valve Y1 (see figure 15 and 16) is closed and the ball valve returns in its rest
position by spring return (back purge).
The clock relay
K2 (type EZ12TI) is piloted for eg. 10 s and switches on and off again the back purge solenoid valve
Y2 in a clock cycle of eg. 1 s.
After this, it is pause time in which the solenoid valve
Y1 is changed over again to the measuring gas sampling. At
the same time, the time-delay relay is switched which – after a delay time of eg. 1 min. - finishes the message
„purging“ and releases again the measurement. This delay time is necessary in order to have active sample gas in
the analyzers during switching over from purging to measuring.
16.4.1.5 Function for ball valve position NO „normally open“
After actuatig the back purge action through K3 (type CT-MXS.22), the message „purging“ appears via the time
relay K1 (EZ12.AV), the control solenoid valve Y1 (see figure 15 and 16) is opened and the pneumatic drive moves
the ball valve into position „back purging“.
The clock relay
K2 (type EZ12.TI) is triggered for eg. 10 s by K3 and switches on and off again the back purge sole-
noid valve Y2 in intervals of eg. 1 s.
After this, it is pause time in which the solenoid valve
Y1 is changed over again to the measuring gas sampling. At
the same time, the time-delay relay is switched which – after a delay time of eg. 1 min. – finishes the message
„purging“ and releases again the measurement. This delay time is necessary in order to have active sample gas in
the analyzers during switching over from purging to measuring.