Signal Description - Agilent Technologies TwisTorr 305-ICQ User Manual

Technical Information

Signal Description

Signal Description Start/Stop: input signal to start or stop the pump.
Connect this input to the +24VDC OUTPUT (V+), in order to start the pump.
Interlock: this input allows the pump to spin when the start input is active; if
inactive, the interlock input stops the pump, disregarding the status of the
start/stop input
Soft Start: input signal to activate the "soft start" to the pump.
The soft start function lasts 15 minutes, but in case the pump for some reason
(i.e. high volume vacuum chamber) cannot reach full speed after those 15 minutes
(or anytime you start the pump), then it will try reaching full speed for an additional
time. By default this additional time is factory set to 15 minutes; this value
(RunUpTime) is selectable by a specific serial command (ref. to the Window
Description chapter).
If full speed is not reached after that time an error condition sets in.
Speed setting: PWM input signal to set the pump speed. The PWM signal
characteristics must be the following:
frequency: 100 Hz +/-20%

amplitude: +24VDC ± 10%

duty cycle range: from 25% to 75% (toff/T) corresponding to a rotational

frequency varying linearly from 700 Hz to the target frequency value set via
serial command (default factory setting 1010 Hz). With duty cycle <25%
rotational frequency = 700Hz, duty cycle >75% rotational frequency = target
frequency value (deviation value <0.25%).
1
NOTE
2
246
The Speed Setting input is able to work also with a PWM signal having an
amplitude equal to 13VDC or to 33VDC. In these conditions, the accuracy
of the speed setting is affected by a deviation value <1%.
Due to the fact that the rotational target frequency value is adjustable via
serial command (refer to the "Windows meanings"), the input condition in
which the PWM duty cycle >75% will ensure a rotational frequency equal to the
one that has been set via the serial command; the default factory setting for
the rotational target frequency is 1010Hz.
Agilent TwisTorr 305-ICQ & 305-IC SF User Manual