Gents, back again for some help. I’m I using RsLogix 500 Micrologix 1500 CPU. I have a total of 6 dampers each fitted with two proximity switches sensing open, closed position, and referenced to the PLC as a state of the damper.
Dampers 1 and 2 are for intake of either outdoor air or return air.
Dampers 3 and 4 are for discharge air either to interstitial space or production room
Dampers 5 and 6 are used for exhaust either from production room or interstitial space
There is a total of 4 cycles that requires all the dampers to be in different position per cycle.
The cycles are:
Cycle1:Outdoor air to production
Cycle2: Outdoor air to Interstitial Space
Cycle3: Return air to interstitial Space
Cycle 4: Off
I need to monitor the damper position for “dampers in position” prior to start of the exhaust fan and supply blower. All good here.
I created 4 predefined words of data (B11:1 to 4) for damper 1 thru 4 and, another four words of predefined data for the exhaust dampers 5 and 6 (B12:1 thru 4).
Based on what the cycle is (Cycle1) I move the required predefined damper data thru indirect addressing for comparison (EQU) with the actual damper position. Once the dampers are in position I trigger a bit “Dampers In Position” and start the supply blower and exhaust. Once Cycle1 calls for the position of the damper I engage a “Damper Position Delay Timer” if the timers DN bit goes hi I trigger a bit “dampers failed to open.
Finally my question.
Q1) I need to trigger an alarm based on which damper failed to open or close, prior to the start up on the unit, most likely when “Damper Position Delay Timer” DN bit is true.
Q2) Once all the dampers are in their correct position, and the supply blower starts, the exhaust blower starts, I need to monitor the positions of the dampers. Meaning once one of the proximity sensor monitoring the state of the dampers position is not in its required state I need to trigger an alarm that the particular proximity sensor has failed.
I’m having a difficult time creating an alarm based on the above statement. Any help is greatly appreciated.
Dampers 1 and 2 are for intake of either outdoor air or return air.
Dampers 3 and 4 are for discharge air either to interstitial space or production room
Dampers 5 and 6 are used for exhaust either from production room or interstitial space
There is a total of 4 cycles that requires all the dampers to be in different position per cycle.
The cycles are:
Cycle1:Outdoor air to production
Cycle2: Outdoor air to Interstitial Space
Cycle3: Return air to interstitial Space
Cycle 4: Off
I need to monitor the damper position for “dampers in position” prior to start of the exhaust fan and supply blower. All good here.
I created 4 predefined words of data (B11:1 to 4) for damper 1 thru 4 and, another four words of predefined data for the exhaust dampers 5 and 6 (B12:1 thru 4).
Based on what the cycle is (Cycle1) I move the required predefined damper data thru indirect addressing for comparison (EQU) with the actual damper position. Once the dampers are in position I trigger a bit “Dampers In Position” and start the supply blower and exhaust. Once Cycle1 calls for the position of the damper I engage a “Damper Position Delay Timer” if the timers DN bit goes hi I trigger a bit “dampers failed to open.
Finally my question.
Q1) I need to trigger an alarm based on which damper failed to open or close, prior to the start up on the unit, most likely when “Damper Position Delay Timer” DN bit is true.
Q2) Once all the dampers are in their correct position, and the supply blower starts, the exhaust blower starts, I need to monitor the positions of the dampers. Meaning once one of the proximity sensor monitoring the state of the dampers position is not in its required state I need to trigger an alarm that the particular proximity sensor has failed.
I’m having a difficult time creating an alarm based on the above statement. Any help is greatly appreciated.
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