%MWx

Loop Status Register

See table below

Bit

Meaning

15

Node Lockout or Parameter Error

14

High Alarm

13

Low Alarm

12

Time since last solution >= solution interval

11

10

Loop is not being solved

9

8

Sign = E stored in Mwx22 , 0=+, 1= -.

7

6

Integral windup limit never set

5

Integral windup saturated

4

Negative values in the equation

3

2

1

Manual/Auto Input

0

%MWx+1

Error Status bits

See table below

Code

Explanation

Register should be checked

0000

No errors, all validations OK

None

0001

SP above4095

%MWx+2

0002

High alarm above 4095

%MWx+4

0003

Low alarm above 4095

%MWx+5

0004

Proportional band below 5

%MWx+6

0005

Proportional band above 500

%MWx+6

0006

Reset above 99.99 r/min

%MWx+7

0007

Rate above 99.99 min

%MWx+8

0008

Bias above 4095

%MWx+9

0009

High integral limit above 4095

%MWx+10

0010

Low integral limit above 4095

%MWx+11

0018

High output clamp above 4095

%MWx+13

0019

Low output clamp above 4095

%MWx+14

0020

Low output clamp above high output clamp

%MWx+13 and %MWx+14

0021

GL below 2

%MWx+15

0022

GL above 30

%MWx+15

0023

Insufficient %Mw register remained

%Mwx

%MWx+2

SP

You must specify the set point in raw data units; the value must be in range of 0~ 4095.

%MWx+3

Mv

Loaded by the block every time the loop is solved; it is clamped to a range of 0 ... 4095, making the output compatible with an analog output module; the manipulated variable register may be used for further CPU calculations such as cascaded loops

%MWx+4

High Alarm Limit

Load a value in this register to specify a high alarm for PV (at or above SP); enter the value in range of 0~ 4095.

%MWx+5

Low Alarm Limit

Load a value in this register to specify a low alarm for PV (at or below SP); enter the value in range of 0~ 4095.

%MWx+6

Proportional Band

Load this register with the desired proportional constant in the range 5 ... 500; the smaller the number, the larger the proportional contribution; a valid number is required in this register for PID instruction to operate

%MWx+7

Reset Time Constant

Load this register to add integral action to the calculation; enter a value between 0000 ... 9999 to represent a range of 00.00 ... 99.99 repeats/min; the larger the number, the larger the integral contribution; a value > 9999 stops the PID instruction calculation

%MWx+8

Rate Time Constant

Load this register to add derivative action to the calculation; enter a value between 0000 ... 9999 to represent a range of 00.00 ... 99.99 min; the larger the number, the larger the derivative contribution; a value > 9999 stops the PID instruction calculation

%MWx+9

Bias

Load this register to add a bias to the output; the value must be between 000 .... 4095, and added directly to Mv, whether the integral term is enabled or not

%MWx+10

High Integral Windup Limit

Load this register with the upper limit of the output value (between 0 ... 4095) where the anti-reset windup takes effect; the updating of the integral sum is stopped if it goes above this value—this is normally 4095

%MWx+11

Low Integral Windup Limit

Load this register with the lower limit of the output value (between 0 ... 4095) where the anti-reset windup takes effect—this is normally 0

%MWx+12

Raw Analog Measurement

The logic program loads this register with PV; the measurement must be scaled and linear in the range 0 ... 4095

%MWx+13

Output Clamp— High

The value entered in this register determines the upper limit of Mv—this is normally 4095

%MWx+14

Output Clamp— Low

The value entered in this register determines the lower limit of Mv—this is normally 0

%MWx+15

Rate Gain Limit (RGL) Constant

the value entered in this register determines the effective degree of derivative filtering; the range is from 2 ... 30; the smaller the value, the more filtering takes place

%MWx+16

solution interval

solution interval, 1 to 255 represent 0.1 to 25.5 second