Edwards GXS Series User Manual

10. Depending on the pump size, it typically takes around 4‑7 minutes to draw through
the 5 litres of the solvent soluon (larger pumps draw the liquid through more
quickly than the smaller pumps). Once the full 5 litres of the solvent soluon have
been drawn through, put the free end of the solvent sucon pipe right down to the
boom of the container holding the 2.5 litres of water. The water will ush
through any solvent soluon remaining in the pump mechanism.
11. The pump typically takes another 2‑4 minutes to draw through the water. Once all
the water has been drawn into the pump, the DP clean process connues with a
purge cycle, drawing air or purge gas into the pump to dry out the mechanism for
the rest of the clean me.
Notes:
1. If monitoring the state of the solvent that exits the pump to determine whether
the pump is clean, take special care because the solvent soluon inially exits the
pump as steam and then as hot liquid with typical temperature of 75 °C.
2. The exhausted liquid will never run clear. The exhausted liquid from a clean
pump has a similar viscosity to water (not thick and viscous) and is a light rust
colour when seen exing the exhaust.
3. Depending on the applicaon, the solvent ush process may need to be
repeated. Contact us for advice.
4. If the pump takes an abnormally long me to draw in uids, there may be a
problem with the high ow purge and solvent ush kit. A blocked orice or leaks in
the solvent sucon pipe or pneumac gas line are the most likely causes.
Invesgate the problem and recfy before connuing to use the solvent ush
procedure. If in doubt, contact us.
Once the DP clean me has elapsed, the dry pumping system will return to green mode/
standby mode sengs. The pump can then be put back on‑process.
To stop the solvent ush process while it is running, enter the DP Clean menu again
using the PDT and select 'DP Clean o'. The pneumac valve will shut, stopping the ow
of solvent into the pump. If DP Clean has been congured to run an inlet purge cycle
aer the clean cycle, sending a 'DP Clean o' command will iniate the purge cycle. To
stop the purge cycle as well, the PDT must be used to select 'DP Clean o' for a second
me.
The DP clean procedure can be congured to suit the user's applicaon. Refer to How to
set up the DP clean on page 141.
4.11 Pump speed control and PID
For some applicaons it is important to be able to adjust the speed of the pump while it
is on‑process, either to a set speed or to control the speed connuously to maintain a
process pressure. The dry pumping system can run both the dry pump and booster at
various speeds while on‑process and it is possible to congure these speeds by a
number of dierent methods. Refer to How to control the pump speed on page 144 for
more informaon about how to set up speed control opons.
The dry pumping system has a built‑in Proporonal-Integral-Derivave (PID) controller.
When the PID funcon is enabled and the pump is on‑process, the PID controller
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M58800880_H - Operaon

Edwards GXS Series Specifications

General

Brand	Edwards
Model	GXS Series
Category	Water Pump
Language	English