Homa HRS Series Original Instruction Manual page 10

3.3.2. Motor
The three-phase asynchronous motor is made from sheet metal with a double-varnished winding wire as well as
the motor shaft with rotor package. The power supply cable is designed for the maximum mechanical load and is
sealed against water pressure from the pumped liquid. The motor cable lead connections are sealed from the
pumped liquid as well. The bearings used are permanently lubricated maintenance-free antifriction bearings.
All models are available with explosion proof motors according to ATEX Ex II 2 G EExd.
General motor data
Operating mode
Insulation class
Degree of protection
Cable length
Shaft sealing HRS
CHRS
Bearing
3.3.3. Control devices
The pump is equipped with various safety and control devices:
Temperature Sensors
The mixers have a set of temperature sensors built in the stator windings.
Standard models have the sensors connected to the motor power supply cable, the wire ends marked T1 and T3.
They must be connected to the safety circuit of the control box in order to provide an automatic re-start of the
motor, when the motor cools.
Explosion proof models with motors up to 15 kW have a set of temperature sensors built-in, with a higher switch-
off temperature, connected to the motor cable, the wire ends marked T1 and T2. They must be connected to a
special relay in the starter box in order to provide manual pump re-start.
All explosion proof models have both sets of sensors built-in, as described above, with wire ends marked T1, T2,
T3. They have to be connected accordingly as described above. The temperature sensor set must be connected
to the switchgear unit so that it switches off if it overheats.
Check of Direction of Rotation
After the electrical connection has been made, check that the agitator propeller is rotating in the correct direction.
As seen from the motor, the propeller must rotate clockwise.
If the direction of rotation of the agitator propeller is incorrect, transpose two of the three conductor phases (L1,
L2, L3) coming directly from the mains.
Beware of rotating propeller!
The moving propeller can crush and sever limbs. Switch off the machine and let the moving parts come to
a rest before maintenance or repair work!
Seal condition sensors oil chamber
Agitator motors in the HRS.../C and CHRS.../C series are fitted as standard with monitoring of the sealing of the
oil barrier chamber.
Two sensors monitor the conductibility of the oil filling. The sensors are to be connected via the connecting cables
with the cable-end designations S1 and S2 in the switchgear to an evaluation instrument with a galvanically
isolated sensor circuit (electrode relay). If the shaft seal leaks, water enters the oil chamber and changes the
resistance of the oil. Response sensitivity should be adjustable from 0-100 kÙ. The standard setting is 50 kÙ. If
this is an antiexplosion design, select electrode relays with intrinsically safe circuits for sensors.
Motor cooling
They are cooled by the surrounding liquid.
3.3.4. Propeller
A self cleaning propeller from stainless steel is used.
40
S1
H (180°C)
IP68
10 m / 15m
NBR
Viton
one grooved ball bearing (suspension side)
one double-row type angular ball bearing (propeller side)