Edwards STP-iS1607 Series - Second Speed Option Control

STP-iS1607 Series Turbomolecular Pump
MT-94E-001-C
Page 65
4
OPERATION
4.9.3 Second speed option
When the second speed option is enabled, second rating speed can be set independently of the
normal rating speed setting. The selection of the second rating speed and normal rating speed are
operated from I/O remote input or serial communication port.
The second speed setting is changed from serial communication port, or STP-Link. (see Section 5.4,
"Command specifications")
Table 13 shows pump status in the state of speed selection.
Pump status
Difference between
Normal Speed and
Second Speed
Setting is more than
approximately 10%
When the rotational speed becomes low, the STP pump enters
BRAKE mode, and then decelerates.
When the rotational speed becomes high, the STP pump enters
ACCEL mode, and then accelerates.
The STP pump will enter the normal mode when the rotational speed
attains within +10% of speed setting.
NORMAL
BRAKE
ACCEL
NORMAL
NORMAL
Pump status
Speed Set Point
Second Speed Set Point
Second Speed Set Point -10%
Second Speed Set Point +10%
Speed Set Point +10%
Speed Set Point -10%
Second speed select
OFF
ON
OFF
Rotational speed
Difference between
Normal Speed and
Second Speed
Setting is
approximately 10%
or less
The rotational speed changes in the normal mode.
NORMAL
Pump status
Speed Set Point
Second Speed Set Point
Second Speed Set Point -10%
Second Speed Set Point +10%
Speed Set Point +10%
Speed Set Point -10%
Second speed select
OFF
ON
OFF
Rotational speed
Table 13 - Second speed function