Bakeout - Edwards nEXT730D Instruction Manual

Table 22 Behaviour of a pump when the power is re-instated after an electrical supply failure
Length of power failure
Power is reinstated before
pump rotational speed falls
below 50%
Power is reinstated after
pump rotational speed falls
below 50% but before re-
generative power ceases
Power is reinstated after
pump rotational speed falls
below 50% and the regen-
erative power ceases

7.9 Bakeout

If the pump (and the vacuum system) are heated, the degassing process will speed up
and the pump will reach ultimate vacuum in the shortest possible time. The pump may
only be heated on the flange with the flange heaters provided for this purpose from the
accessories. Heating the pump will also prevent condensation of vapours inside the
pump.
B8J200880_D
300812671_002_C3
B8J200880_D - Operation
Control mode
Either parallel or seri-
al control mode
Either parallel or seri-
al control mode, timer
disabled
Either parallel or seri-
al control mode, timer
enabled
Either parallel or seri-
al control mode
Page 87
Behaviour of pump
Regenerative power maintains all output signals
during the power failure. The pump will ramp to
its designated speed as quickly as possible after
the power has been restored.
Regenerative power maintains all output signals
during the power failure. As the timer is disa-
bled, the motor controller will go into fail condi-
tion as soon as speed falls below 50% and will
display flashing error code 0. When the power is
reinstated, the pump will not ramp up until the
error is cleared. To clear the error, send a stop
command (either parallel or serial, depending on
the control mode), then send a start command
to ramp the pump up to the designated speed.
Regenerative power maintains all output signals
during the power failure. If power is reinstated
before the timer period expires, the pump will
ramp up to its designated speed as quickly as
possible. If the timer period expires, the motor
controller will go into fail condition and will dis-
play flashing error code 3. As above, when the
power is reinstated, the pump will not ramp up
until the error is cleared. To clear the error, send
a stop command (either parallel or serial, de-
pending on the control mode), then send a start
command to ramp the pump up to the designa-
ted speed.
Regenerative power ceases and fails to maintain
output signals. When power is reinstated, the
pump with parallel control will automatically re-
start if the start control on the logic interface is
set to start. The pump with serial control will re-
quire a new start command to ramp the pump
up to the designated speed. Any fail signals that
were triggered during the regenerative power
period are lost when the power is reinstated.
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