Watlow CAS - Manual (Page 14)

4 CAS User’s Guide
Introduction
Voltage inputs: 0-12V, 0-10V, 0-5V, 0-1V, 0-500mV, 0-100 mV with
scaling resistors.
Source Impedance: for 0-60 mV, measurements are within
specification with up to 500 ohms source resistance.
Digital Inputs
Number: 8
Configuration: 8 selectable for remote job selection. Digital input #8 is
only used for external alarm acknowledge.
Input Voltage Protection: Diodes to supply and common. The source
must limit current to 10 mA for override conditions.
Voltage Levels: <1.3V=Low; >3.7V=High (TTL).
Maximum Switch Resistance to Pull Input Low: 1 Kohms.
Minimum Switch Off Resistance: 11 Kohms.
Digital Outputs
Number: 34
Operation: Open collector output; On state sinks to
logic common.
≤
20 mA for 35 outputs,
≤
40 mA for a single output,
Ι
Total
≤
700 mA.
Function: Selectable as alarm latched/unlatched.
Off State Leakage Current: <.01 mA to DC common.
System Digital Outputs
System Digital Outputs: 1 Global Alarm, 1 CPU watchdog.
Operation: Open collector output; On state sinks to logic common.
≤
20
mA for 35 outputs,
≤
40 mA for a single output,
Ι
Total
≤
700 mA.
Range Input Resistance
0-12 V 85K ohms
0-10 V 50 K ohms
0-5 V 40 K ohms
0-1 V 7.4 K ohms
0-500mV 6.2 K ohms
0-100 mV 1.2 K ohms
0-20 mA 3 ohms
0-10 mA 6 ohms