Cx output 1 type none/off, Cx output 2 type none/off – West Control Solutions MRC 9000 User Manual

Page 236

Edition 3

Rev G

Section 13

13-5

CASCADE control uses two “control blocks”. The output of one controller is the setpoint of a second controller.

Ratio and bias (see Steps 20 & 21) need to be applied to the connecting setpoint. Because of the interaction

between controllers, cascade control will only apply to controllers 1 and 2, or 3 and 4, used in pairs, with 1 and 3

being the first controller.

FEEDFORWARD adds a 0-100% value to the PID output. When feedforward is used, the feedforward source

(Step 22) is scaled to provide a 0-100% value to work with the loop output of 0-100%. Depending on the limits of

the input, and the scaling, the FF-term may be limited to less than 100%.

SP + PID adds a term that makes the output primarily proportional to the setpoint, but with PID capability added.

This is used primarily for flow control.

4. Press the

to advance to the next parameter, OUTPUT 1 TYPE.

Cx OUTPUT 1 TYPE

NONE/OFF

Selections

NONE/OFF

ON/OFF DIRECT

ON/OFF REVERSE

PID DIRECT

PID REVERSE

5. Press the

to advance to the next parameter, OUTPUT 2 TYPE.

Cx OUTPUT 2 TYPE