SKF SFD - Annual Inspections; MLT (Micro Logic Timer) Dryers; PLC (Programmable Logic Control) Dryers; PC (Pneumatic Control) Dryers

8. CAUTION: Slowly pressurize system
9. Check air line fittings for leaks and repair as necessary
10. Observe dryer operation for proper function as described above in “Pneumatic Control”
ANNUAL INSPECTIONS
MLT (Micro Logic Timer) Dryers
Operational Check:
1. Check electrical power to MLT
2. Check all air connections for leaks or damaged signal lines
3. Unit should exhaust (discharge) every two minutes
4. Refer to flow diagram detailed in FLOW DIAGRAM
5. If dryer fails to cycle, unplug timer, and manually cycle dryer several times turning small brass
screw from 12 o’clock position to 2 o’clock position
(approximately ¼ turn) located on spool valve. If dryer cycles
manually, return brass screw back to original vertical position
and reference “Troubleshooting SFD Air Dryer Systems”.
PLC (Programmable Logic Control) Dryers
Operational Check:
1. Check electrical power to PLC (Green light on switch)
2. Check all air connections for air leaks or damaged signal lines
3. Unit should exhaust (discharge) every 45 seconds
4. Refer to flow diagram detailed in FLOW DIAGRAM
5. If dryer fails to cycle refer to TROUBLE SHOOTING SFD AIR DRYER
SYSTEMS
PC (Pneumatic Control) Dryers
Operational Check:
1. Check pneumatic connections for leaks, broken pilot signal lines, etc.
2. Unit should exhaust (discharge) approximately every 60 seconds
3. Refer to flow diagram detailed in FLOW DIAGRAM
4. If dryer fails to cycle, refer to TROUBLESHOOTING SFD AIR DRYER SYSTEMS
Brass Screw
12