Emerson Tescom ER5000 Series, User Manual, Page: 227 / 248

ER5000 —
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Internal Variables
ER5000 Inner Loop Tuning Variables
NOTE NOTE
CAUTION CAUTION
WARNING WARNING
Variable #6 (ID_COMPENSATED_INTERNAL_SENSOR) is 16-bit
when the controller is in ER5000 mode (Jumper J9 = OFF, variable #120
(ID_MODE_ER3000_ER5000) => 0). When the controller is in ER5000
mode, a value of 6400 counts is 0% and 59200 counts is 100%. To convert
between counts and percent, use the following formulas:
• value_percent = (value_counts16 - 6,400) * 100 / 52,800
• value_counts16 = (value_percent * 52,800 / 100) + 6,400
Variable #6 is 12-bit when the controller is in ER3000 mode
(Jumper J9 = ON, variable #120 (ID_MODE_ER3000_ER5000) => 1).
When the controller is in 12-bit ER3000 mode, a value of 400 counts
is 0% and 3700 counts is 100%. To convert between counts and
percent, use the following formulas:
• value_percent = (value_counts - 400) * 100 / 3,300
• value_counts = ( value_percent * 3,300 /100) + 400
03 ID_INNER_D_COEF1
This is the D-term, Derivative constant, for the inner loop.
06 ID_COMPENSATED_INTERNAL_SENSOR
This is the compensated internal sensor value, after
temperature compensation, zero and span have been
applied to the raw signal. A value of 6400 is 0% and 59200 is
100%. When the controller is in ER5000 mode, this variable
records data in 16-bit mode, which gives more accurate data
acquisition than variable #44 (ID_FEEDBACK).
28 ID_INNER_INTEGRAL_CONSTANT
This is the I-term, Integral Constant, for the inner loop.
29 ID_INNER_INTEGRAL_MAXIMUM
This is the maximum value allowed for the Integral sum on
the inner loop.
30 ID_INNER_INTEGRAL_SUM
This is the value of the Integral sum for the inner loop. It is
formed by multiplying the Integral constant times the error
and summing the result with the previous value for the
Integral sum.
35 ID_INNER_PROPORTIONAL_CONSTANT
This is the P term (Proportional Constant) for the inner loop.
50 ID_INNER_INTEGRAL_MINIMUM
This is the minimum value allowed for the Integral sum on the
inner loop.
66 ID_INNER_INTEGRAL_DEADBAND
This is the inner loop minimum error required for the Integral
sum to be changing in value. Often it is set to zero and has
no effect. However, if it is desirable to stop integrating
once the error is reduced below a certain value, for instance
when using an external dome-loaded regulator which has
hysteresis, then this parameter should be set to the minimum
acceptable error.