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Overview
311200D
3
Overview
Usage
The leak detector monitors air operated double dia-
phragm pumps for diaphragm rupture or other leaks that
may contaminate the fluid being pumped. The system is
made up of a main control box and two liquid detection
sensors. The sensors are screwed into the air side of
each diaphragm on the pump. When liquid is sensed by
either one of the sensors, an alarm will sound, indicating
a diaphragm rupture has occurred. The control box also
has the ability to control an external device such as an
alarm, light, or an air solenoid via an onboard relay.
During normal operation, the LED indicators on the con-
trol box and each sensor will flash once per second,
indicating proper operation. If a system fault or a leak is
detected, an alarm will sound and the LED on the con-
trol box will blink three times per second. See table,
page 8.
Component Identification and
Description
Before you install the system, you should be familiar
with the parts discussed in the following paragraphs.
Sensors
The sensors are mounted on the pump to detect liquid
on the air side of the diaphragm. See F
The sensors use two methods of detection: optical and
conductive.
Having both conductive and optical sensors allows the
sensor to detect as many liquids as possible. When both
sensors are in air, both lights (blue and yellow) flash
once per second.
When the sensor is immersed in a conductive liquid, the
blue LED will stop flashing. When the sensor is
immersed in a liquid compatible with the optical sensor
the yellow LED will stop flashing.
Control Box
The control box powers and monitors the sensors and
sound the alarm when a leak is detected.
The control box powers and reads the sensors every
second. If the sensors detect liquid, the control box will
alarm and set it’s fault relay.
Relay
The relay has two sets of contacts that can be used to
indicate an error by turning off a valve, lighting a light,
etc. The contacts are located at J4 on the circuit board.
See F
There are two separate sets of Common, NO/NC con-
tacts labeled CRS.
•
C (Common)
•
R is Reset, which is connected to Common during
normal operation. (NO)
•
S is Set, which is connected to Common when an
error is detected. (NC)
For example, if an air valve was held open during nor-
mal operation, the power to the valve would enter at C
and exit at R. During normal operation C and R are con-
nected and would open if liquid were detected by a sen-
sor. This would stop the pump. Power must be
maintained to the control box for the pump to operate.
When the control box loses power it will set the relay.
Both sets of CRS contacts are floating contacts and are
electrically isolated from each other and the electronics
on the control board. They do not supply power and
should be used as a switch only.
Always disconnect the power supply from the con-
trol box prior to cleaning the pump.
Sensors
Definition
Conductive
The two metal pins on the sensors.
Controls the blue light and its signal
is the white wire.
Optical
The plastic dome in the center of the
sensor. Controls the yellow light and
its signal is the green wire.