Table of Contents
Advertisement
10.2.3 Moisture switches and leakage switches
Non-Ex version:
A moisture switch and a leakage switch are mounted in a non-Ex
pump. The moisture switch is placed in the top cover and the
leakage switch is in the chamber above the shaft seal. See,
Sectional drawings, motors
section C-C and E-E.
Ex version:
A moisture switch and a leakage switch are mounted in an Ex
pump. The moisture switch is placed in the top cover and the
leakage switch is in the stator housing. See,
motors
section C-C and D-D.
All switches in both non-Ex and Ex versions are hardwired from the
pump to IO 113. If moisture or a leakage is detected, they break the
electric circuit. This generates both a hardware and a software
alarm in IO 113, and the alarm relay opens.
Moisture- and leakage switches are motor protection devices
protecting the motor from moisture or leakage.The switches are
non-reversing, and they must be replaced after being released.
The moisture- and leakage switches are connected in a separate
circuit and to the control cable. See Appendix. They are also to be
connected to the safety circuit of the separate pump controller.
10.2.4 Thermistors
The standard pump range has Klixon switches; however, pumps
with PTC thermistors are also available as Factory Product Variants
(FPV).
The thermistors can be used as motor protection devices to monitor
stator temperature instead of thermal switches, and must be
connected to the thermistor relay in the control cabinet.
The operating voltage of PTC thermistors is 2.5 - 7.5 V.
Checks after electrical connection
1. Use a multimeter to check whether the circuit resistance is
below 150 Ω per thermistor.
2. Use a multimeter to check whether the insulation between circuit
and stator housing is outside the range.
3. Carry out similar measurements at the end of the power cable.
Pt1000 temperature sensor
The Pt1000 temperature sensor is available as an accessory or an
FPV.
The Pt1000 sensor is primarily used for the monitoring of bearing
temperature, but it can also be used in the stator.
In case of overheating, the Pt1000 sensor trips an alarm and
disconnects the power supply at a preset temperature.
The bearing temperature monitoring system is only availa-
ble as an option.
The sensor resistance values are the following:
•
1000 Ω at 20 °C (68 °F)
•
1385 Ω at 100 °C (212 °F)
•
approximately 1078 Ω at room temperature.
The temperature limits are the following:
•
90 °C (194 °F): warning for bearing temperature
•
130 °C (266 °F): pump stop caused by high bearing temperature
•
150 °C (302 °F): pump stop caused by high stator temperature.
In Ex-approved pumps, the maximum acceptable alarm
temperature in the bearing sensors is 100 °C for the lower
bearing (shaft end) and 120 °C for the upper bearing.
Checks after electrical connection
1. Use a multimeter to check whether the resistance at room
temperature (20 °C [68 °F]) is approximately 1078 Ω.
2. Use a multimeter to check whether the insulation between the
circuit and the stator housing is outside the range.
3. Carry out similar measurements at the end of the power cable.
During the pump check, the Pt1000 sensor must be connected to a
recording device.
10.2.5 Pump vibration sensor (PVS 3)
The PVS 3 sensor monitors the vibration level to protect the pump
and the pipe network against damage.
A change in the vibration level indicates an abnormal situation.
Make sure that a service inspection is carried out before the pump
or the pipe network is damaged.
Sectional drawings,
SM 113
The SM 113 module is used for collecting and transferring sensor
data. SM 113 works with IO 113 through power line communication
using the Grundfos GENIbus protocol.
SM 113 collects data from the following devices:
•
•
•
•
IO 113
The IO 113 module is the interface between a pump with analogue
and digital sensors and the pump controller. The most important
sensor data are indicated on the front panel.
One pump can be connected to IO 113.
With the sensors, IO 113 is a galvanic separation between the
motor voltage in the pump and the connected controller.
IO 113 enables the following functions:
•
•
•
•
Measurement of insulation resistance
IO 113 measures the insulation resistance between a stator winding
and ground:
•
•
•
Pumps are fitted with S-tube
pellers are wet-balanced to reduce vibrations during oper-
ation. If these pumps are started with the pump housing
containing air, the vibration level can be higher than in
normal operation.
3 current sensors, 4-20 mA
3 Pt1000 thermal sensors
1 PTC thermal sensor
1 digital input.
SM 113 is fitted with a 2.7 kΩ resistor to avoid false sen-
sor alarms in the IO 113.
overtemperature protection
monitoring the sensors for analogue measurement of:
- motor temperature
- pump vibrations
- stator insulation resistance
- bearing temperature
- moisture in motor.
stopping the pump in case of alarm
monitoring the pump remotely through RS485 communication
(Modbus or GENIbus).
resistance above 10 MΩ = OK
resistance between 10 MΩ and 1 MΩ = warning
resistance below 1 MΩ = alarm.
®
®
impellers. The S-tube
im-
27
Advertisement
Table of Contents
