Watson-Marlow 520Du - Manual (Page 61)

Watson-Marlow 520DuN IP66/NEMA 4X User Manual 61
This pump passes all EMC compatibility requirements with up to 25m (82ft) of the
cable type specified above. Beyond this distance it is the user’s responsibility to
ensure the pump’s safe and reliable operation under remote and automatic control.
Do not strap the control and mains power cables together.
The 0V lines on this pump are mains transformer-isolated from ground (floating
ground). It can be connected to isolated 0V or grounded 0V interfaces. The TTL
(transistor transistor logic) outputs 1 and 2 used here are composed of two states:
nominally 0V and 5V; but in practice <0.4V (<16mA) and 2.4-5V (<0.4mA). They
are not suitable for driving relays. If a relay is to be driven by the TTL signal, it must
be done as described under 22.10 Logic outputs, below.
RS232 control
RS232 network control is available via a 9-pin D-connector wired as below.
RS232 is the mode provided to allow the pump to be controlled by computers and
process controllers. It can control every function of the pump, and pass data back
to the controller for closed loop operation. Up to 16 pumps can be individually con-
trolled.
Recommended control cable: 7 strands 0.2mm, 24AWG, screened, circular, up to 4-
core. The cable screen should be earthed through the metalwork of the shell.
This pump passes all EMC compatibility requirements with up to 3m (10ft) of the
cable type specified above. Beyond this distance it is the user’s responsibility to
ensure the pump’s safe and reliable operation under remote and automatic control.
The 0V lines on this pump are mains transformer-isolated from ground (floating
ground).