Control Responses 4.2; Direct/Reverse Operation Of Control Outputs; Control Capability - Partlow MIC 8200 Installation And Operation Manual

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Control Capability 4.1

A variety of user programmable control features and capabilities are available including:
• AutoTune
• Time Proportioning Control
• Position Proportioning Control
• Dual Output Control
• Automatic Transfer
• Process Re-transmission
The capabilities available in a specific unit are dependent upon the hardware options specified
when the instrument is ordered. Refer to Appendix C (page 58) for the decoding of the
instrument model number. Current proportioning control cannot be implemented if a current
output was not ordered. Position proportioning cannot be implemented if two relays (Outputs
1 and 2) and the option have not been ordered. The available output types and quantity of
each are as follows:
Type of Output
* SPST mechanical relay output
* SSR Driver
* mADC current output
The maximum number of SPST relay and/or SSR driver outputs available on a single instru-
ment is three. Relay and SSR drivers may be assigned as either control or alarm outputs.
The mADC current output(s) may be assigned control or process value retransmission
output functions.

Control Responses 4.2

Each instrument may be configured to provide 3 mode proportional control. Proportional
control is provided with Proportional Band, Integration, and Derivative responses. The PID
parameters are defined as follows:
P (Proportional)
I (Integration)
D (Derivative)
Manual Reset is provided for use in lieu of, or in conjunction with automatic reset. A cycle
time adjustment parameter is provided for use with each time proportioning control output.
Direct/Reverse Operation of Outputs 4.3
Direct operation is typically used with cooling applications. On-Off direct output(s) will turn on
when the process variable exceeds setpoint. Proportional direct output(s) will increase the
percentage of output as the process value increases within the proportional band.
Reverse operation is typically used with heating applications. On-Off reverse output(s) will
turn off when the process variable exceeds setpoint. Proportional reverse output(s) will
decrease the percentage of output as the process value increases within the proportional
band.
• On-Off Control
• Current Proportioning
• Alarm Functions
• Auto/Manual Switching
• Setpoint Adjustment
Quantity Available
Up to three
Up to three
Up to two
Proportional Band
Automatic Reset
Rate
Out 1 Out 2
Pb1 Pb2
ArS1 ArS2
rt1 rt2