MKS 356 Micro-Ion Plus Series, Instruction Manual

Page: 53 / 76

Operation
Micro-Ion
®
Module Instruction Manual - 356007-GP
53
In
stallation
O
per
a
tion
Maintenance
Before You
Begin
PC - Process Control
1. Make sure the module is properly installed and the power is ON.
2. Use Table 3-7 to record the activation pressure, activation direction,
and hysteresis for each relay.
3. Refer to the following example process control (PC) command
sequence to program the
pressure at which the relay will activate:
The example PC command sequence causes relay 1 to activate when
vacuum pressure decreases to 1.01 x 10
–1
.
Example PC command from host:
#01PC1 1.01E–01
↵
Response from module:
*01 PROGM OK
↵
The “PC1” command identifies process control relay 1. The “PC2”
command identifies process control relay 2.
PCP - Process Control
Polarity
In default mode, relays activate with decreasing pressure and deactivate at
a 10% higher pressure than the activation pressure, as illustrated in
Figure 3-9 on page 37.
The example process control polarity (PCP) command causes relay 1 to
activate with increasing pressure.
Example PCP command from host:
#
↵
Response from module:
*01 PROGM OK
↵
• The “PCP1” command identifies process control relay 1. The “PCP2”
command identifies process control relay 2.
• The + sign causes the relay to activate with increasing pressure.
• The – sign causes the relay to activate with decreasing pressure.
PCH - Process Control
Hysteresis
• Default hysteresis is 10% below activation pressure if the relay activates
with increasing pressure (+).
• Default hysteresis is 10% above activation pressure if the relay activates
with decreasing pressure (–).
The example process control hysteresis (PCH) command causes relay 1 to
deactivate when increasing pressure is 20% lower than the activation
pressure, if relay 1 polarity activates with increasing pressure (+).
Example PCH command from host:
#01PCH1 20
↵
Response from module:
*01 PROGM OK
↵
• The “PCH1” command identifies process control relay 1. The “PCH2”
command identifies relay 2.
Valid values are any percentage, from 5% to 100%, that is divisible by 5.