2-Stage Burner, Analog Output - Siemens RWF55.5 User Manual

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Cooling controller
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5.2.4 2-stage burner, analog output

In this case, a digital standard signal switches the second stage on via the analog
output (terminals A+ and A-) when reaching switch-on threshold HYS1 and off at the
lower switch-off threshold HYS2.
Figure 11: Control sequence of 2-stage burner, analog output
If the controller is set to cooling mode, the respective values of HYS4, HYS5 and HYS6
apply.
Starting from a high actual value, the controller now controls the connected cooling
equipment in low-fire operation. In high-fire operation, the second stage and thus the
cooling output are controlled via relays K2 and K3 or the analog output. The response
threshold (q) calculates automatically (now in the reverse sense) the point from which
the cooling output is to be increased.
User Manual RWF55...
5 Operating modes
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CC1U7867en
05.11.2013