Technical Specifications

Step 5: Position Control Limits

Setup Wizard Procedure

Step 5: Position Control Limits Wizard

To use this:

1. Enter values as required in Figure 71, referring to the descriptions given in

“Position Limits Parameters” on page 75.

Figure 71 Position Control Limits Wizard

2. Select Next.

Position Limits

Parameters

Tight Shutoff Below

(%)

If the valve position Set Point is less than this value the valve is

forced to fully close. As a general practice this is set between 1

and 3 to minimize seat leakage. The dead band is a function of

this setting, typically between 1/10th and 1/100th of the setting.

The TSB feature is designed to prevent leakage of valves when

the Set Point is 0%.

Full Open Above (%) If the valve position Set Point is more than this value the valve

is forced to fully open.

Position Lower Limit

(%)

The valve position Set Point cannot be less than this value. This

prevents the valve from closing. Use only when required by the

control strategy.

Position Upper Limit

(%)

The valve position Set Point can not exceed this value. This

prevents the valve from closing.