Ulvac UTM300B, Instruction Manual

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6.5 Variable Speed Operation
6.5.2 Operation from Start-up to Low Speed Rotation
This is the procedure until low-speed rotation is achieved when the speed setting is made with
the pump stopped.
6.5.2.1 Logic interface Operation
(1) Start-up begins when the 6.2.2 "Start-up Preparation Sequence in logic interface" is
complete.
(2) Set rotation to low speed via RS-485 interface. Once it is set, it does not need to be set
each time.
(3) Input the "LOW SPEED" signal (Refer to Table 6-6) from the logic interface.
(4) Input the "START" signal from the remote-control connector (Refer to Table 6-6).
(5) The pump starts to accelerate.
(6) When the rotational speed reaches 80 % of low speed value, the "NORMAL" signal turns
on.
(7) When the pump speed reaches the set low speed value, acceleration stops and the pump
speed is maintained.
※
The same operation occurs if the "LOW SPEED" signal is input after the "START" signal
is input but before the pump speed reaches the set low speed value.
6.5.2.2 RS-485 interface Operation
(1) Start-up begins when the 6.2.3 "Start-up Preparation Sequence in RS-485
communication" is complete.
(2) Set rotation to low speed via RS-485 communication.
(3) "LOW SPEED" command is input via RS-485 communication.
(4) "START" command is input via RS-485 communicaton.
(5) The pump acceleration starts. Status is changed from "STOP" to "ACCELERATION".
When the rotational speed reaches 80 % rated value, status is changed from
"ACCELERATION" to "NORMAL".
(6) When the pump speed reaches the set low speed value, acceleration stops and the pump
speed is maintained.