Figure 22 Carb Function Block Examples - Honeywell HC900 Reference Manual

Function Blocks
CARB Carbon Potential Function Block
Example
F igure 22 shows Function Block Diagrams using a CARB function block.
H
Application:
To clean a carbon probe periodically
by blowing air across it for a specific
time.
In this configuration, a periodic timer
generates a pulse a designated time
interval which suspends automatic
control and energizes a relay output
to cause air flow for a probe burn off
cycle. Timers determine the probe
burn-off period and allow time for
the probe recovery before returning
the loop to automatic control.
Configuration Notes:
Select probe Mfg.. type
O2 probe input: 0 to 2 V.
(0 to 2000 range)
Select T/C type J or K etc..
116
Carbon Potential Probe Burn-off
Timing Diagram
PTMR Output
MDSW Output
Auto
Off delay #1
Burnoff Time
Time Delay to AUTO

Figure 22 CARB function block examples

HC900 Hybrid Control Designer Function Block Reference Guide
Auto
Manual
Off delay #2
Revision 11
2/07