Sensaphone CELL682 - Manual (Page 49)

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Chapter 7: Machine-to-Machine Control
• Setting peer-to-peer trigger values too close can cause output oscillations. Peer-
to-peer commands are an advanced feature and should be well thought out.
Do not use them for critical applications where the risk is unacceptable.
• All peer-to-peer control actions will use a wireless message packet.
saMple application
Suppose you had a well and a pump which were several miles apart. When the
pump runs, it fills the well. Your goal is to maintain a certain level in the well. If
you place one Cell682 unit at each location you can have two peer-to-peer events
accomplish your goal. In addition, you can use the Cell682 inputs to monitor other
key items such as:
• Well level too low
• Well level too high
• Pump failure
• Power failure
• Generator on
• Temperature
CELL 682
W i r e l e s s A l a r m s
CELL 682
W i r e l e s s A l a r m s
Figure 3: Well and Pump Control via Machine-to-Machine Commands
Let’s suppose the well level is 25’ and you need to maintain the level between 5’
and 20’. The first thing you would need is a level transducer in the well. Next, pro-
gram your two machine-to-machine events into the Cell682 located at the well.
The first would be to turn ON the pump if the level is Less-Than 5’. The second
event would be to turn the pump OFF if the level is Greater-Than 20’. Consider the
rate at which the well fills when the pump is running, in order to account for the
machine-to-machine command delay time between the Cell682 units. Also note
that machine-to-machine control is completely independent of alarm processing,
so you can also trip high or low-level alarms based on the well level.