Milltronics miniranger plus - Page 37

7ML19981CJ01 MiniRanger Plus Page 37
Functional
pump sequencing: pumps 1 and 2 operate in lead lag fashion alternating
roles on successive pump cycles (first pump on, to all
pumps off) . Specifically, pump 1 responds to relay 1
setpoints and pump 2 responds to relay 2 setpoints during
the first pump cycle. During the second cycle, pump 2
responds to relay 1 setpoints and pump 1 responds to
relay 2 setpoints.
Note:
Relays programmed for pump control will not energize within 10 seconds
of a MiniRanger Plus power up, or within 10 seconds of each other.
Open Channel Monitoring (OCM)
Note:
OCM calculation is an optional feature. MiniRangers with the OCM feature
have this icon
on the front.
The MiniRanger Plus can convert a head measurement into a flow rate using a
nine breakpoint head vs. flow characterisation curve; this chart is usually
available from the manufacturer of the weir or flume or other primary
measuring device (PMD). Parameters P001 and P600 must both be set to 1 in
order to program the MiniRanger Plus for flow measurement. All nine
breakpoints must be used (set with P610 and P611). Zero head is set with
P006 and corresponds to zero flow; maximum head is set with P007 and
corresponds to maximum flow set in P604. Please refer to Open Channel
Monitoring (OCM) within the Applications chapter for further details (page 53).
Once the MiniRanger Plus is programmed for open channel monitoring, the
mA output is scaled to represent the flowrate and the RUN mode display will
show the flowrate.
The MiniRanger Plus provides a pulsed relay contact to drive an external
totalizer. Relay 2 is automatically set to run an external totalizer when the
unit is programmed for OCM. See Open Channel Monitoring (OCM) on page
53 for programming details.
Relay 1 can still be programmed normally when OCM is used.
Setpoints
Relay setpoints are in the units as programmed (P005).
Operation, P001 = 1, 2 or 3
The setpoints are measured from the bottom up, referenced to zero or empty
(P006).
Operation, P001 = 4
The setpoints are measured outward from the transducer face.