1. Standard: The tip and barrel are connected to the normal (SEC)
power outlet earth via a 220R/0.01 Filter.
2. Floating Earth (FE): When you insert the jack into the socket beside the iron
flex entry socket the normal (SEC) earth connection is interrupted.
The iron tip is now in Circuit with the aligator clip provided. This clip is for attachment to the PCB earth raił when strict equi potential soldering conditions are required such as for MOS devices.
Removing the jack restores standard earthing.
SYMPTOM
CHECK
CURE
1. Element fails to heat (LED Bar Not operating.)
Check Power Switch Check 3A Fuse Cneck Primary 240 VAC.
Check Secondary 28 VAC.
Switch ON Replace if blown Check above, cord or if any power at power point — Re-ctify. Check transformer primary resistance. Approximately 48 R. Remove lead from PCB secondary resistance 30R Replace transformer if faulty.
2.
Element fails to heat (LED Bar operating)
Check element resistance at socket end or inside iron.
Check supply to iron on PCB connector to iron
Check connector to iron Check Ul.
Remove iron from socket Measure resistance 60W = 9-1 OR 30W = 19-20 R Replace if necessary.
Measure between red and white wires on connector: should be Approximately 24 VAC when Heat LED ON.
Check Triac for open Circuit Triac ON when 0.3V on "Gate" Replace if faulty 6.8V on pin 7 if element off, 2-3 mV with element ON Replace if faulty.
Check for open Circuit Thermocouple
Iron Over Heats (no Control)
LED Bar operating (Test quickly so tip is not ruined)
5. LED Bar irregular
Measure resistance at connector pin 1-2R(iron removed), should be 1-5R when iron is at room temperaturę. If open Circuit — replace element and thermocouple assembly.
Fix if necessary.
4. LED Bar off but iron heating
Check, LED Bar connector to PCB
(TEST OUICKLY SO THAT TIP IS NOT RUINED)
(Switch Power ON and OFF if necessary)
Check U2
Check for short Circuit Triac
Check Ul, U2,
Replace if faulty.
Measure gate volts.
0.3V DC on 2 mV off.
Replace if necessary.
AT pin7: 6.8 VDC element 'off' 2.0 m VDC element'on' Replace if necessary.
Check connector to PCB and wires
Clean, repair of replace.
If problem does not respond please return to -
SCOPE LABORATORIES
3 Walton Street, Airport West, Vic. 3042 AUSTRALIA Tel: (03) 338 1566 Tlx: 38318 (SCOLAB)