Watlow CAS200 - Manual (Page 69)

CAS200 User’s Guide Chapter 4: Setup
Watlow Anafaze 57
Input Scaling Low Reading
Use this menu to enter the input level that corresponds to
the low process value you entered in the previous menu.
For linear inputs, the low reading is a percentage of the full
scale input range. For the pulse input, the low reading is in
Hertz.
The full scale range of the linear input type is -10 to 60mV
where 0mV corresponds to 0% and 60mV corresponds to
100%. The actual signal is scaled to be within this range
with scaling resistors. For pulse inputs, it is 0 to 2000Hz.
Selectable values: Depends on the Input Type, -99.9 to
999.9 when Input Type is set to Linear; 1 to 2000Hz when
Input Type is set to Pulse.
Input Filter
The CAS200 has two different types of input filter:
• A noise rejection filter that rejects high frequency
input signal noise. This filter keeps a "trend log" of
input readings. If a reading is outside the filter's
"acceptance band", and later readings are within the
acceptance band, the CAS200 ignores the anomalous
reading. (The acceptance band for thermocouples is 5
degrees above and 5 degrees below the input reading.
For linear inputs, it's 0.5% above and 0.5% below the
input reading.) If later readings are also outside the
acceptance band, the CAS200 accepts the anomalous
reading and calculates a new acceptance band. (You
cannot adjust this input filter.)
• A standard resistor-capacitor (RC) filter that lets you
dampen the input response if inputs change
unrealistically or change faster than the system can
respond. If the input filter is enabled, the process
variable responds to a step change by going to 2/3 of
the actual value within the number of scans you set.
Selectable values: 0 to 255 scans
CHANNEL PROCESS UNITS
CHANNEL NAME ALARM STATUS
01 INPUT SCALING
LO RDG ? 0.0% FS
CHANNEL PROCESS UNITS
CHANNEL NAME ALARM STATUS
01 INPUT FILTER ?
3 SCANS