Watson-Marlow 720UN and 720SN User Manual
18
UN, SN
10 Connecting this product
to a power supply
A well regulated electrical mains supply is required along with cable connections con-
forming to the best practice of noise immunity. It is not recommended to site these
drives alongside “dirty” electrical mains supplies such as 3-phase
contactors and inductive heaters without special attention being paid to
unacceptable mains-borne noise.
The voltage selector is mounted in the switchplate at
the rear of the pump, protected from water by the
720N module. The module must be removed to allow
access to the switchplate. See 19.1
720N module re-
moval and replacement
. Set the voltage selector to
115V for 100-120V 50/60Hz supplies or 230V for
200-240V 50/60Hz supplies. Always check the volt-
age selector switch before connecting the mains sup-
ply. Make suitable connection to an earthed,
single-phase mains electricity supply. To comply with
Safety Standards, the mains plug must be a separa-
ble plug (not a locking type).
We recommend using commer-
cially available supply voltage
surge suppression where there
is excessive electrical noise.
Power cable
: The pump is supplied fitted with either of two cable glands and ap-
proximately 2.8m of power cable. The European cable is to Harmonised code H05RN-
F3G0.75, used with our gland part number SL0128 which is suitable for an outside
cable sheath diameter of 4-7mm. The north American cable is to type SJTOW 105C
3-18AWG VW-1 used with our gland part number SL0123 which is suitable for an out-
side cable sheath diameter of 7-9mm.
Power cables of NEMA 4X specification pumps are fitted with a standard US mains
power plug. IP66 specification pumps are supplied with no plug. Wiring a mains plug
must only be undertaken by suitably skilled, qualified personnel.
European
North American
line
brown
black
neutral
blue
white
ground
green/yellow
green
Conductor coding
