Figure
10
shows the electrical connections when
using external impulse contacts (momentary
contacts) for start/stop push button station.
L1
L2
L3
K
Start
K
Stop
P2
Fig. 10
External impulse contacts
5. Starting the pump
5.1 Vent the piping system
After the pump has been installed and the
electrical connections made, the piping system
must be vented.
Never operate the pump dry - the
system must first be filled with liquid
Caution
and vented.
Do not vent the piping system through
Note
the pump.
Instead, follow these steps:
1. Fill and pressurize the system with liquid,
and vent all trapped air from the piping by
suitable means.
2. If any isolation valves are used, make sure
they are OPEN.
WARNING
If the vent screw is to be loosened,
care should be taken to ensure that
the escaping scalding hot liquid does
not cause personal injury or damage
to components (see fig. 12).
10
K
L3
L2
P1
T3
T2
T1
5.2 Check the direction of shaft rotation
Applies to 460 V and 575 V two-speed models
only
(The direction of rotation of three-speed pumps
is checked by means of the fault finding chart,
page
13
and page 14).
1. Make sure that the power is OFF.
2. Unscrew and remove the vent plug located
at the center of the nameplate.
3. Insert a small, flat-blade screwdriver into the
slot in the end of the motor shaft (see fig. 12).
Rotate the shaft with the screwdriver to make
sure it does so freely.
4. Bump the pump and watch to see which
direction the shaft rotates. The shaft must
rotate in the counterclockwise direction as
shown on the nameplate (see fig. 11).
5. If the pump shaft is rotating incorrectly,
disconnect the power and interchange any
two power leads in the terminal box.
6. Check once again for proper
counterclockwise rotation. When it is rotating
correctly, replace the vent plug.
Fig. 11
Vent plug and direction of rotation
Fig. 12
Removing the vent plug
Direction of
rotation
Vent plug
Inspection
Inspection scre
screw/vent plug