Watlow Series SD31 PID with Optional Countdown Timer - Manual (Page 33)

Wa t l o w S e r i e s S D 3 1
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31
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C h a p t e r 6 O p e r a t i o n s
Display Parameter Name
Description
Settings Range
(Integer values for Modbus
in parentheses.)
Default Modbus*
(less 40,001
offset)
Read/Write
Appears if:
Note: Parameters appear on the Operations Page only if activated from the Programming Page. See page 16 for Operations Page defaults.
Note: Some values will be rounded off to fit in the four-character display. Full values can be read with Modbus.
* Low register numbers contain the two higher bytes; high register numbers contain the two lower bytes of the four-byte integer.
Decimal precision is implied at three decimal places unless otherwise noted.
** This value multiplied by 100 equals the percent power.
Caution: Writing to registers continuously, such as ramping set points via comms, will damage the SD31 EEPROM memory. See page 59.
[rA;Cl]
[rA.CL] Rate Cool
Set the PID rate time in minutes for the
cool outputs.
0.00 to 9.99 minutes
(0000 to 99990)
0.00: disabled
0.00 *230, 231
R/W At least one output is
set to
[CooL], [Cl;m]
is set to [`PId], and
[Unit] is set to
[``US].
[dE;CL]
[dE.CL]
Derivative Cool
Set the PID derivative time in minutes
for the cool outputs.
0.00 to 9.99 minutes
(0000 to 99990)
0.00: disabled
0.00 *230, 231
R/W At least one output is
set to
[CooL], [CL;m]
is set to [`PId], and
[Unit] is set to
[``SI].
[dB;Cl]
[db.CL] Dead Band Cool
An offset of the cooling proportional
band from the set point.
0 to 999
(0000 to 999000) 0 *281, 282
R/W At least one output is
set to
[Cool] and
[CL;m] is set to
[`PId].
[C;hyS]
[C.hyS]
Cool Hysteresis
Set the control switching hysteresis for
on/off control. This determines how far
into the “on” region the input needs to
move before the output actually turns
on.
1 to 999°F if [`Sen] is set
to [``tc] or [`rtd]
(1000 to 999000)
0.000 to 999.9 if [`Sen] is
set to [`ma] or [uolt]
(0000 to 999000)
1
1.000
*236, 237
R/W
*238, 239
R/W
At least one output is
set to
[CooL] and
[CL;m] is set to
[on;oF].
[ProP]
[ProP] Proportional Term
View the active proportional term for
PID diagnostics.
0.000 to 1.000**
(0000 to 1000) NA 258 R Any output is set to
[heat] or [Cool].
[``it]
[ it] Integral Term
View the active integral term for PID di-
agnostics.
0.000 to 1.000**
(0000 to 1000) NA 259 R Any output is set to
[heat] or [Cool].
[``dE]
[ dE] Derivative Term
View the active derivative term for PID
diagnostics.
0.000 to 1.000**
(0000 to 1000) NA 260 R Any output is set to
[heat] or [Cool].