Table of Contents
Advertisement
The motors have to be connected using cable and line entries
which meet the requirements of EN 50019 for terminal
compartments in type of protection "increased safety" and for
which separate test certificates have been issued.
All unused openings shall be closed with plugs which have also
obtained the requisite test certificates and are marked
accordingly.
5.5.2
Connecting the power cable
Electrical connection shall be effected by suitably
trained personnel only.
The power cable must be connected to the appropriate
terminals in the terminal box as shown on the wiring diagram in
the terminal box.
The correct direction of rotation of the motor is ensured by a
mains with a clockwise rotating field. If the motor has been
connected correctly, it would run in anti-clockwise rotation if it
could be viewed from the side of the bare shaft end (hydraulic
end).
When connecting the pump to the power supply, make sure to
observe the clearances between conductive components of
different potential stipulated by EN 60079-7.
Connection of the earthed conductors (terminal box and
motor housing) shall be in accordance with IEC 60079
(DIN VDE 0165) and IEC 60364 (DIN VDE 0100), depending
on the mains type.
5.5.3
Connecting the control cables
The wiring diagram supplied in the terminal box is limited to
motor connection and thermal monitoring by means of PTC
resistors. Other connections, e.g. an integrated PT100 sensor
for measuring the rotor space temperature, must be effected as
described in the supplementary operating manual of the
accessories in question (e.g. motor standstill heater).
If the motor is equipped with PTC resistors, control terminals
10/11 are connected and the information "PTC 180 / --- " or "PTC
180 / 110" is shown on the name plate.
The PTC resistors must be connected to a tripping unit as
shown on the above-mentioned wiring diagram. If motor
overload protection as stipulated by IEC 60079 (DIN VDE 0165)
relies exclusively on PTC resistors, the tripping unit used must
be rated in accordance with Directive 94/9/EC, Annex II,
Section 1.5.5 and EN 1127-1, e.g. tripping unit with PTB
approval seal 3.53 PTC/A. (The PTB approval seal 3.53-PTC/A
confirms compliance of the electrical data at the interface
between the resistor circuit and the tripping unit and approval
of the tripping unit for use with PTC resistors for thermal
monitoring of explosion-proof electrical equipment.)
The tripping unit is not explosion-proof and
Caution
therefore has to be installed outside the
hazardous area.
5.5.4
Monitoring equipment
For installation and commissioning of the following monitoring
equipment
PTC monitoring
monitoring of rotor space temperature
monitoring of rotor space filling level
Please refer to the separate operating manuals.
If plant conditions are such that the pump could
Caution
run dry due to a lack of liquid, the plant operator
must provide an appropriate monitoring device. See section
7.2.1.
All monitoring equipment must meet the requirements of
Directive 94/9/EC, Annex II, Section 1.5.5, and
EN 1127--1. If any non--approved monitoring equipment is
used, successful functional testing must be demonstrated and
documented separately. Such equipment must be included in
the operator's monitoring routines.
5.5.5
Potential equalisation
To avoid sparking, potential equilisation
Caution
must be ensured between the pump and
any metal objects located in the vicinity. Sparking may cause
explosion.
Providing potential equalisation
The screw terminal for the potential equalisation conductor is
fitted on the outside of the motor housing.
Motor sizes DE 90, 112 and 132
The terminal consists of a pressed--in square base with fitted
clamp and a screw (M6) with spring washer. The potential
equalisation terminal complies with VDE 0170 and is marked
with the earth symbol.
Fig. 9 Earth symbol
The conductor must be connected in a suitable manner as set
forth in EN 60999--1:2000
Nominal cross--section:
Max. tightening torque:
Fig. 10 Connecting the PE conductor
Motor sizes DE 160 and 200
The conductor must be connected in a suitable manner as set
forth in EN 60999--1:2000
Nominal cross--section:
Max. tightening torque:
Earthing terminal
Fig. 11 Connecting the PE conductor
5.6
Pump operation with frequency inverter
The canned motors can also be operated with
frequency inverters. Make sure to observe the design
data of the motor in this case. As frequency inverters generate
an additional temperature rise in the motor, the PTC resistors in
the motor winding have to be connected to safeguard explosion
protection. This prevents an inadmissible heat build-up in the
motor.
The motors are suitable for frequency inverter operation in the
frequency range from 25 Hz (min.) to 50 or 60 Hz (max.),
depending on the nominal motor frequency they are designed
for.
Secochem-Ex
2
10 mm
3,5 Nm
Earthing terminal
Motor housing
2
25 mm
3,5 Nm
Motor housing
13
Advertisement
Table of Contents
