Lake Monitors FlowStat ES Sensor (Plastic) - Manual (Page 6)

Installation - Electronic (Pulse Output Only)
The FlowStat pulse output circuit is a three-wire DC-powered design that
transmits a frequency proportional to flow rate. The circuit operates on 5-
24 V
DC and will consume a maximum of 25 mA from the power supply.
1. Connect the red wire (pin 1 for units with the electronic disconnect
option) from the sensor to the positive terminal of the 5-24VDC
power supply.
2. Connect the black wire from the transmitter (pin 2 for units with the
electronic disconnect option) to the negative terminal of the 5-24
V
DC power supply.
3. Connect the green wire from the transmitter (pin 3 for units with
electronic disconnect) to the (+) pulse input of the data acquisition
device. This connection may be labeled "Pulse In" or "DC Input"
on some devices.
4. If applicable, connect the negative side of the power supply to the
negative side of the pulse input.
5. Apply power to the system.
6. If everything is operating correctly, the data acquisition device should
begin "counting" pulses when fluid starts flowing through the sensor.
If the data acquisition device is not “counting”:
check wiring terminations for good connections
verify correct supply voltage and current
7. The installation should be complete. The relationship between the
frequency output and flow rate is shown in the graphs above.
(6)
Flow Rate vs. Frequency Output
Standard 1/2" NPTF Units
0
10
20
30
40
50
60
0 2 4 6 8 10 12 14 16
Flow Rate (GPM)
F
re
q
u e n
c y
(H
z )
Flow Rate vs. Frequency Output
Standard 3/4" & 1" NPTF Units
0
10
20
30
40
50
60
0 10 20 30 40 50 60
Flow Rate (GPM)
F
re
q
u e n
c y
(H
z )
Installation - Electronic (Relay Output Only)
1. Connect the red wire from the sensor to the positive terminal of the
12-35 V DC power supply.
2. Connect the black wire from the transmitter to the negative terminal
of the 12-35 V DC power supply.
3. (Versions with stainless steel sensor body only) Be sure to properly
ground the FlowStat sensor by using the ground screw shown
in Illustration 2 to connect the sensor body Earth ground.
This step may be
unnecessary if the
piping system that the
flow sensor is plumbed
into is already connected
to Earth ground.
4. Wire the appropriate
relay contacts to the load
that is to be switched per Table 1 below.
5. If the unit is operating correctly, the green power indication LED
and the red relay status LED should illuminate after the DC supply
voltage is turned on. As fluid flow is increased above the factory-
adjusted set point, the red relay status LED should turn off.
If the LEDs do not illuminate when power is applied:
check wiring terminations for good connections
verify that the DC supply voltage is between 12 and 35 V DC
Table 1.: Wiring Connections
(7)
Wire Color Connection
Red +12-35 V DC
Black DC Ground
Green Relay Common
White Relay Normally Closed Contact
Brown Relay Normally Open Contact
Illustration 2
GROUND
SCREW