![background image](http://html1.mh-extra.com/html/campbell/0871lh1/0871lh1_instruction-manual_3754707027.webp)
25
3
Input/Output Specification
3.1
Input/Output Pin Designations
Table 2. Input/Output Pin Designations
Signal Name
Con-
nector
Pin
Input or
Output
Definition Current
Wire
Gauge
24VDC A
Input 18-29.5
VDC**
1.5 Amp Max at
28VDC 20
24VDC Return
B
Input ----
----
20
Case Ground
C
Input ----
----
20
RS-422 High
D
Output Per
RS-422
Spec
Per RS-422 Spec
20-24
RS-422 Low
E
Output Per
RS-422
Spec
Per RS-422 Spec
20-24
Ice F
Output
Ground Active (1.5 VDC Max)
0.5 - 50 mA
20-24
Open Inactive
Status G
Output
Ground Active (1.5 VDC Max)
0.5 - 50 mA
20-24
Open Inactive
**Ice will be correctly detected between these voltages. Proper probe de-icing, however, is only guaranteed when
input voltage is 24VDC or greater.