Siemens Milltronics BW500, Руководство по эксплуатации

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Operation
8.9 Relay Output
BW500 and BW500/L
102
Operating Instructions, 12/2016, A5E33482052-AD
8.9 Relay Output
The BW500 offers five single pole single throw (SPST) relays that can be assigned (P100) to
one of the following alarm functions, the BW500/L offers two relays of the same type:
● rate: relay alarms on high and/or low material flow rate.
● load: relay alarms on high and/or low belt load.
● speed: relay alarms on high and/or low belt speed.
● differential speed
1)
: relay alarms if second speed signal outside high and/or low alarm
setpoints.
● diagnostic: relay alarms on error condition as it is reported. See “Troubleshooting”.
● PID
1)2)
: PID control setpoint deviation
● batch pre-warn
1)
● batch setpoint
1)
For rate, load, and speed alarm functions, the high and low alarm setpoints (P101 and P102
respectively) are required and must be entered in the appropriate units. The high alarm setpoint
acts as the setpoint deviation alarm for relays programmed for PID setpoint deviation.
The on/off actuation at both high and low setpoints is buffered by the damping (P080) and the
programmable dead band (P117), to prevent relay chatter due to fluctuations. The relay is
normally energized; holding the normally open (n.o.) contact closed (can be programmed for
reverse operation, P118). Upon an alarm condition, the relay is deenergized and the relay
contact is opened. Once in alarm, the relay remains in alarm state until the alarm condition is
removed.
1)
Not available with BW500/L
2)
Is offered only if the PID system (P400) is enabled.
Example:
P014 = 2m/s, design speed
P100 = 3, belt speed
P101 = 100% (2 m/s)
P102 = 20% (0.4 m/s)
P117 = 2% (0.04 m/s)