Pump Controllers; Thermal Switch, Pt1000 And Ptc Thermistor; Wio Sensor (Water-In-Oil Sensor); Moisture Switch - Grundfos SL1 Series Installation And Operating Instructions Manual

8.2 Pump controllers

SL1 and SLV pumps can be connected to the following Grundfos
pump controllers for level control:
LC controllers are for one-pump-installations and LCD controllers
are for two-pump installations.
• LC 107 and LCD 107 with air bells
• LC 108 and LCD 108 with float switches
• LC 110 and LCD 110 with electrodes
• Grundfos DC and DCD.
For further information on controllers, please see the installation
and operation instructions for the selected controller or go to
www.grundfos.com.

8.3 Thermal switch, Pt1000 and PTC thermistor

All SL1 and SLV pumps have thermal protection incorporated in
the stator windings.
Pumps without sensor
Pumps without sensor have a thermal switch or a PTC thermistor.
Via the pump controller safety circuit, the thermal switch will stop
the pump by breaking the circuit in case of overtemperature
(approx. 150 °C). The thermal switch will reclose the circuit after
cooling. For pumps equipped with a PTC thermistor, connect the
thermistor to either the PTC relay or the I/O module to break the
circuit at 150 °C.
The maximum operating current of the thermal switch is 0.5 A at
500 VAC and cos φ 0.6. The switch must be able to break a coil in
the supply circuit.
Pumps with WIO sensor
Pumps with WIO sensor have either a thermal switch and a
Pt1000 sensor or a PTC thermistor in the windings, depending on
the installation site.
Via the pump controller safety circuit, the thermal switch or the
thermistor will stop the pump by breaking the circuit in case of
overtemperature (approx. 150 °C). The thermal switch or the
thermistor will reclose the circuit after cooling.
The maximum operating current of both the Pt1000 and the
thermistor is 1 mA at 24 VDC.
Non-explosion-proof pumps
When closing the circuit after cooling, the thermal protection can
restart the pump automatically via the controller. Pumps from
4 kW and up sold in Australia/New Zealand are fitted with a PTC
thermistor.
Explosion-proof pumps
Warning
The thermal protection of explosion-proof pumps
must not restart the pump automatically.
This ensures protection against overtemperature in
potentially explosive environments. In pumps with
sensor this is done by removing the short circuit
between terminals R1 and R2 in the IO 113. See
Electrical data in the IO 113 installation and
operating instructions.
Warning
The separate motor-protective circuit breaker/
controller must not be installed in potentially
explosive environments.

8.4 WIO sensor (water-in-oil sensor)

The WIO sensor measures the water content in the oil and
converts the value into an analogue current signal. The two
sensor conductors are for power supply and for carrying the
signal to the IO 113. The sensor measures the water content from
0 to 20 %. It also sends a signal if the water content is outside the
normal range (warning), or if there is air in the oil chamber
(alarm). The sensor is fitted in a stainless-steel tube for
mechanical protection.
Fig. 10 WIO sensor
8.4.1 Fitting the WIO sensor
Fit the sensor next to one of the shaft seal openings. See fig. 10.
The sensor must be tilted into the motor's direction of rotation to
ensure that oil is led into the sensor. Make sure that the sensor is
submerged in the oil.
8.4.2 Technical data
Input voltage: 12-24 VDC
Output current: 3.4 - 22 mA
Power input: 0.6 W
Ambient temperature: 0-70 °C
See also the installation and operating instructions for IO 113 on
www.grundfos.com.

8.5 Moisture switch

All pumps are fitted with a moisture switch as standard with the
moisture switch being connected via the supply cable, see
section 8. Electrical connection, and connected to a separate
circuit breaker.
The moisture switch is positioned in the bottom of the motor.
If there is moisture in the motor, the switch will break the circuit
and send a signal to the IO 113.
The moisture switch is non-reversing and must be replaced after
use.
The moisture switch is connected to the monitoring cable, and it
must be connected to the safety circuit of the separate pump
controller. See section 8. Electrical
The motor-protective circuit breaker of the pump
controller must include a circuit which automatically
Caution
disconnects the power supply in case the protective
circuit for the pump is opened.
connection.
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