PD6600 Series Loop-Powered Process Meters
Instruction Manual
35
Pump Control (
PUMPCTRL
)
The pump control output is used in situations where
the relays are used to control pumps. There are two
options available for controlling pumps: on-off (
ON-
OFF
) and pump alternation (
ALTERN
).
ON-OFF
will turn the relay on at a programmed
on
point and off at a programmed
off
point. Setting the
on
point higher than the
off
point will make the output ac-
tivate on a high PV value; setting the
on
point lower
than the
off
point will make the output activate on a
low PV value. The relay will reset automatically.
For pump control applications where two similar
pumps are used to control the level of a tank or a well,
it may be desirable to have the pumps operate alter-
nately. This prevents excessive wear and overheating
of one pump over the lack of use of the other pump.
Pump alternation uses both relays in tandem to alter-
nate between two similar pumps. The
ALTERN
menu
is only available under Output 1 and will automatically
set Output 2 to pump alternation as well. Use the
pump
Alternation Time
setting (
ALT.TIME
) to control
the alternation based on runtime in addition to level
cycles.
On/Off Pump Control (
ON-OFF
)
When programming a single pump to turn on and off,
the
on
and
off
points must be programmed. The relay
will activate at the
on
point and deactivate at the
off
point. On and off delays may be programmed to delay
the activation or deactivation of the relay by a certain
number of seconds after reaching either the
on
point
or
off
point.
Pump Alternation (
ALTERN
)
Pump alternation sets the two relays to alternate
every time the first
on
point (
ON 1
) is reached. The
active relay will turn off once the first
off
point (
OFF
1
) is reached. If the PV reaches the second
on
point
(
ON 2
), the other relay will also turn on. The second
relay will turn off once the second
off
point (
OFF 2
) is
reached and the first relay will remain active until the
first
off
point (
OFF 1
) is reached.
On and off delays may optionally be programmed for
each
on
and
off
point to delay the activation or deacti-
vation of the relays by a certain number of seconds
after reaching either the
on
point or
off
point.
For pumps that typically remain on extensively, the al-
ternation time (
ALT.TIME
) parameter sets a period of
relay on-time after which the relays should alternate.
For example, if the alternation time is set to one hour,
pump 1 will turn off after one hour of runtime regard-
less of the level reading, at which point pump 2 be-
comes the active pump. Pump 2 will run until one
hour has passed, or the tank has reached a desirable
level; whichever happens first. By using the proper
on/off points, the alternation can be set up so that the
first pump on is the first pump off. This is desirable
when the two pumps are of similar rating.
RLY 1
PUMPCTRL
PUMP
ON-OFF
PUMP
DELAY
DELAY
ON
TIME
0000 SEC
DELAY
OFF
TIME
0000 SEC
ON
+00,070.00
ON
GAL
Flashes
Units
OFF
GAL
OFF
+00,060.00
Flashes
Units
RLY 1
PUMPCTRL
PUMP
DELAY2
DELAY
ON
TIME
0000 SEC
DELAY
OFF
TIME
0000 SEC
ON 2
+00,090.00
ON 2
GAL
Flashes
Units
OFF 2
GAL
OFF 2
+00,080.00
Flashes
Units
ON 1
+00,070.00
ON 1
GAL
Flashes
Units
OFF 1
GAL
OFF 1
+00,060.00
Flashes
Units
PUMP
DELAY1
DELAY
ON
TIME
0000 SEC
DELAY
OFF
TIME
0000 SEC
PUMP
ALT.TIME
000.00
HHH.MM
PUMP
ON-OFF
PUMP
ALTERN
