the process only after any remaining flammable gases or vapours have been
purged from the pump and exhaust line.
▪
If liquids that produce flammable vapours could be present in the pump foreline
then the inert gas purge to the pump should be left on all the time this liquid is
present. Flammable liquids could be present in the foreline as a result of
condensation or may be carried over from the process.
▪
When calculating the flow rate of inert gas required for dilution, consider the
maximum flow rate for the flammable gases or vapours that could occur. For
example, if a mass flow controller is being used to supply flammable gases to the
process, assume that a flow rate for flammable gases that could arise if the mass
flow controller is fully open. The inert gas purge flow rate should be continually
measured and if the flow rate falls below that required, then the flow of flammable
gases or vapours to the pump must be stopped.
The Vacuum Pump and Vacuum System Safety publication P40040100 is available from
us or the supplier.
5.6 Remote operation using 15-way D connector
It is possible to operate the pump remotely using the 15
‑
way D type connector fitted on
the panel at the side of the pump.
The 15
‑
way D connector is insulated to ensure that it remains protected in the event of a
single fault condition.
The controls available are as follows:
▪
Run/Standby
▪
Run
‑
(Runs pump at standard speed 100%).
▪
Standby
‑
(Pump is not running but is ready and awaiting a remote signal for
operation).
▪
Idle
‑
(Runs pump at 67% speed).
▪
Boost
‑
(Runs pump at 116%) intermittent use only (not for continuous operation).
See note below for further information on this mode of operation.
▪
OK Signal
Figure: Logic interface schematic on page 24
shows which connections to make to
enable these functions.
The Run/Standby switch (
Figure: General view on page 9
, item 9) should be in the
Standby position for remote operation. The idle and boost modes are only available with
remote operation.
To completely remove electrical power from the pump, the plug should be removed
from the electrical connector (
Figure: General view on page 9
, item 7).
Note:
Boost operation is not recommended for the pump as a permanent operation mode, as
increased bearing loads will reduce the life of the pump bearings. Please consult us if the
boost mode is intended to be used as the limits of operation are application dependent.
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A73101880_F - Operation