Sterling SDA 1000-5100 Benutzerhandbuch

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Large Dehumidifying Dryers  
Troubleshooting 
49 
Chapter 7:  Troubleshooting 
7-1   Introduction 
The utmost in safety precautions should be observed at all times when working on or around 
the machine and the electrical components. All normal trouble-shooting must be 
accomplished with the power off, line fuses removed, and with the machine tagged as out of 
service.  
Before making haphazard substitutions and repairs when defective electrical components are 
malfunctioning, we recommend that you check the associated circuitry and assemblies for 
other defective devices. It is common to replace the obviously damaged component without 
actually locating the real cause of the trouble. Such hasty substitutions will only destroy the 
new component. Refer to wiring diagrams and schematics. 
7-2   Basic Troubleshooting 
 
Problem 
Possible Cause 
Corrective Action 
 Dirty Filters  
Clean or replace filters.  
Desiccant beds contaminated by 
material or plasticizer leaking 
into the system.  
Replace desiccant  See page 46. 
Blower fuse(s) blown.  
Fix problem and Replace fuse(s). 
Overload tripped. 
Fix problem and reset the 
overload.  
Little or no air 
coming from 
process delivery 
tube.  
Blower fins filled with dust or 
contaminants. 
Remove blower side plate, clean 
baffles, replace. 
Suction in delivery 
tube, pressure from 
the return tube.  
Phase is reversed on power drop 
coming into the dryer. 
Stop the Dryer.  
If the dryer was connected to the 
drying hopper, check to see if the 
desiccant and process air heater 
has been contaminated with resin. 
If so, replace the desiccant and 
remove any resin carry-over. 
Otherwise, change the phase of 
two legs of the three-phase power 
drop.  Never change the phase at 
the motor starters unless only one 
of the two blowers is rotating 
improperly. 
Process heaters are faulty. 
 
Check for open or shorted heaters. 
Replace if required. Check the 
fuses. 
 Solid-state temperature controller 
faulty. 
Replace. 
Loss or reduction of 
process air 
temperature. 
 
Process temperature was adjusted 
in error by plant personnel. 
Make sure that plant personnel are 
aware of the proper temperature 
set point. A sign posted next to the 
control would be helpful.