Tjernlund CPC-2 Constant Pressure Controller (Discontinued) 8504091 Rev A 03/01 User Manual
Tjernlund products, inc

TJERNLUND PRODUCTS, INC.
1601 Ninth Street • White Bear Lake, MN 55110-6794
PHONE (800) 255-4208 • (651) 426-2993 • FAX (651) 426-9547
Visit our web site • www.tjernlund.com
CPC-2 SOFTWARE VERSION 3.02.02 ADDENDUM
1. New Data Display - | V 0.00 0.00I | Data on this line.
| | Messages on this line.
" " = key pad open; "F" = fault; " " = Inducer is in manual mode
2. New Fault Bandwidth - While the CPC-2 continues to maintain the setpoint pressure
within +/-0.01" w.c., a fault will now occur after the actual pressure is +0.05" w.c. or
-0.02"w.c. away from setpoint for a duration of 90 seconds.
3. New Appliance Staging - Automatically stages appliances for a minimum of 10 seconds
when multiple appliances "call" simultaneously. Pressure must reach and remain within
bandwidth of pressure setpoint for 4 seconds before next appliance is allowed to fire.
4. Control Algorithm Change - The speed of acceleration towards the setpoint (gain) has
been increased to improve the CPC-2 response time. The control architecture will now allow
over shoot into the above setpoint region, resulting in fewer faults.
5. Control Algorithm Change - At start up, the computer program now has continuous
Inducer acceleration towards the setpoint. Originally, the program increased the Inducers
RPMs in four steps. That approach prevented over shooting the setpoint but it took longer to
get there.
6. Restart Function - After a fault the CPC-2 will shut down the appliance(s). After a period
of 60 seconds it will attempt a restart. If fault occurs again, then the CPC-2 will lock the
appliances out until serviced. (Mechanical faults are excluded from restart).
7. Transducer Pressure Range Change - The model TD-2 transducer will now sense
between +0.15" w.c. and -0.60" w.c. This increases the gain when operating at low system
setpoints.
8. Fault Codes Expanded - New fault codes and messages let the service person know what is
wrong and when it happened. The last four faults are automatically stored chronologically.
The fault duration has been expanded to 90 seconds from 60 seconds.
SEE CPC-2 FAULT CODES ON REVERSE SIDE