Second Speed Option - Edwards STP-iS2207 Series Instruction Manual

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.
Difference between
Normal Speed and
Second Speed Setting
is more than
approximately 10%
Difference between
Normal Speed and
Second Speed Setting
is approximately 10% or
less
STP-iS2207 Series Turbomolecular Pump
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.
Rotational speed
Speed Set Point +10%
Speed Set Point
Speed Set Point -10%
Second Speed Set Point
Pump status NORMAL
Second speed select
The rotational speed changes in the normal mode.
Rotational speed
Speed Set Point +10%
Speed Set Point
Speed Set Point -10%
Second Speed Set Point
Pump status
Second speed select
Table 13 - Second speed function
Pump status
BRAKE NORMAL ACCEL
OFF ON
NORMAL
OFF ON
Second Speed Set Point +10%
Second Speed Set Point -10%
NORMAL
OFF
Second Speed Set Point +10%
Second Speed Set Point -10%
OFF
MT-89E-001-C
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