Honeywell DCP552 Mark II user manual TP-A7 TP-A6 TP-A5 TP-A4 TP-A3 TP-A2 TP-A1

Chapter 6. OPERATION

• The point￿￿￿￿￿ at￿￿￿￿￿￿￿￿which￿￿￿output reverses￿￿￿￿ ￿￿￿￿￿￿￿(lower￿￿limit￿￿￿⇔ upper limit) during auto- tuning￿￿ is determined from the SP and PV values at AT startup as follows.

￿￿￿￿￿￿￿ ￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿

• Auto-￿￿tuning performed using a variable parameter PA08 setting of 3 or 4 and a PA93 setting of 3 or 4 cause auto-tuning to be performed on SP, PID parameters tP-A1to tP-A7, in order.

tP-A7
tP-A6	￿￿￿￿
tP-A5
tP-A4
tP-A3
tP-A2
tP-A1

•Auto-tuning can be started by the AT key, external switch input and by transmission. The AT LED flashes during auto-tuning.

•Auto-tuning terminates without writing PID constants and the AT LED goes off when any of the following conditions occur.

•Operation is terminated by pressing of the AT key.

•Operation is terminated by an external switch input.

•Operation is terminated by transmission.

•Mode change occurs. (When the MANUAL mode is invoked; the READY mode is invoked by setting PA08 and PA93 to 1 or 2, the RUN mode is invoked by setting PA08 and PA93 to 3 or 4.)

•When PV goes outside the range.

Handling Precautions

•Auto-tuning cannot be performed in CH2 on a model with CP compensation.

•Auto-tuning does not operate normally when the equipment to be controlled is not connected.

•The time required for auto-tuning depends on the equipment controlled.

•When auto-tuning is executed, control is terminated , lower and higher limit outputs are repeated several times and PV fluctuates. When equipment failure may be caused by PID fluctuations, set the PID value manually.

If just PID value can not be got in case of control object, sets PID value with manual.

•Variable parameter PA08 and PA93 settings make values set at the start of auto-tuning valid. A change in the PA08 and PA93 settings made during auto-tuning execution is ignored. The new value is valid in the next auto-tuning operation.

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