Handpieces - Pace ST 65 Operation & Maintenance Manual

Corrective Maintenance

Handpieces

The following "Heater Assembly Checkout Procedures" (Table 4) is applicable to
all PACE SensaTemp handpieces used with the ST 85 system except for the TT-
65 and DTP-80 handpieces. Refer to the applicable manuals for troubleshooting
procedures pertinent to that handpiece.
Perform the procedures with the handpiece heater at room temperature. If the heater
is warm, resistance readings will be different from those shown. Disconnect the
handpiece from the power source. Use a meter to check resistance across the
handpiece connector plug pins as outlined in the "Checkout Procedure" column.
Symptom Checkout Procedure
Handpiece Check resistance - Pin 2 to
does not Pin 5. Refer to "Heater
heat. Specifications" column.
If resistance is high - -
Check resistance - Pin 3 to
Pin 6. If circuit reads open -
-
Handpiece Check resistance - Pin 3 to
overheatin- Pin 6. Resistance should be
g; LED off. 110 ohms. If resistance is
less than 105 ohms - -
Fuse blows Check resistance - Pin 2 to
when unit is Pin 5. Refer to "Heater
turned on. Specifications" column. If
resistance is low - -
No Ground Check resistance - Pin 4 to
on Tip. a NEW Tip. Resistance
should be less than 2 ohms.
If not - -
Table 2. Heater Assembly Checkout Procedures
20
Cause Solution
Open Heater Replace Heater
Assembly.
Open Sensor Replace Heater
Assembly.
Shorted Sensor Replace Heater
Assembly.
Shorted Heater Replace Heater
Assembly & Fuse.
Oxidation in Clean Heater
Heater Bore. Bore using
appropriate wire
brush.
Defective Replace Heater.
Heater
Heater Specifications
P S - 8 0 = 8-10 ohms
SX-80 = 8-10 ohms
SX-70 = 8-10 ohms
TP-65 = 9-11 ohms
TJ-70 = 6 - 8 ohms
Connector
Plug Pinouts