Goulds Pumps 3171 - IOM - Manual (Page 28)

If the first pump fails to keep up with demand, or not come on at all, then a continued rise in the level
turns both pumps on. Both pumps run until the low-water level is reached. If both pumps are unable to
keep up with the demand, then an optional high-water alarm switch can be supplied in the alternator to
close a switch if the water level rises past the second pumps on the level. This switch can be wired into a
customer-supplied alarm horn or light.
APEX high level alarm
The APEX high level alarm is an independent device used to sense fluid level and close a switch that
activates a separate alarm. The switch is mounted on a pipe above the support plate. The pipe must extend
into the sump 4 to 6 in. (10 to 15 cm) below the required actuation point. As the liquid level rises in the
pipe, trapped air causes bellows inside the switch to inflate and trip a microswitch. The switch can then
activate a light, horn, relay, solenoid valve, or other electric device.
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2
3
5
6
7
4
1. High water alarm
2. Reducing adapter, 0.5 in. x 1.0 in. (13.0 mm x 26.0 mm)
3. Nipple, 1.0 in. (26.0 mm)
4. Coupling, 1.0 in (26.0 mm)
5. Pit cover
6. Pipe, 1.0 in (26 mm), 8.0 in. (204 mm) shorter than the pump length
7. Cut the pipe 2.5 in. (64 mm) below the required switch actuation point
Magnetrol displacer-type liquid level switch
The Magnetrol displacer-type liquid level switch is closed by a magnetic seal inside a sealed tube. Switch
operation is controlled by the buoyancy of weighted displacers suspended on a spring. As liquid level rises,
the resulting change in buoyancy moves the spring upwards. The spring movement causes a magnetic
sleeve to attract a pivoted magnet, closing the actuating switch. Refer to installation guide supplied by the
manufacturer for proper installation and configuration.
Float ball switches
Float balls are individual switches that are used in multiple configurations to control the pump circuit. The
float balls are suspended in the sump to the desired control level. When the fluid level rises to the float
ball, the switch begins to float. The float is either anchored to a pipe or weighted. This allows the switch to
tilt when the fluid continues to rise. When the float tilts, a switch closes that you can use in order to turn
the pump on, activate a high-level alarm, or control any other electrical device.
Install the Square D 9036 simplex and 9038 duplex float controls
A single float and rod assembly is used with the 9036 float switch on a simplex unit or the 9038 duplex
alternator. Refer to the wiring diagram from the manufacturer for the correct wiring of the switch.
If a pit cover is supplied with the pump, the float switch support pipe (435) and the upper rod guide (337)
are installed by the factory. If the pit cover is supplied by others, you must locate, drill, and tap the holes
before you install the switch.
Installation (Continued)
26 Model 3171 Installation, Operation, and Maintenance Manual