T460 - T470H; Lc60H - Elma T310H Service Manual

How to replace components
on the generator print
15.2
Transistors
Elma Order No.
How to proceed
Varistor
Elma Order No.
Diodes
Elma Order No.
Resistances
Elma Order No.
76
T460 – T470H; LC60H
Units made since 1997 are fitted with transistors of the type
MJE 13009.
The old BUW41B transistors in units made before 1997 can be
replaced by the new MJE 13009.
In case of a short circuit of the transistors always replace both
transistors. The transistors must have the same amplification
factor, as otherwise the unequal charging of the transistors can
overheat and destroy them.
The transistors are preselected by Elma. Spare part deliveries
always contain transistors with equal amplification factor.
If the fuse on the generator print is blown check the
transducers.
200 000 8098
1. Loosen the holding clamps of the transistors.
2. Remove the generator print from the bottom plate.
3. Unsolder and remove the transistors.
4. Check the diodes for short circuits; replace if necessary.
5. Check the resistances 100 Ohm and 1.2 Ohm for
throughline; replace if necessary.
6. Solder in new transistors.
7. Mount the generator back onto the bottom plate.
8. Fasten the transistors to the clamps on the bottom plate.
Caution: Use new insulating sleeves for the transistors.
The transistors must lie evenly on the bottom plate.
9. Adjust the generator (see section 16.ff).
There can occur a short circuit in the varistor due to extreme
peak voltages or to a mains overvoltage (fuse and varistor
faulty). The varistor is visibly broken and black. Usually, no
other components are faulty.
115V: 200 000 6132 / 230V: 200 000 5064
The diodes (BA 159 or 1N4007) can be faulty in case of a short
circuit of the transistors.
BA 159: 200 000 6123
1N4007: 200 00 5001
The resistances 1 Ohm / 0.5W; 100 Ohm / 0.5W or
47 kOhm / 1W can be faulty due to a short circuit of the
transistors.
Check with ohmmeter.
1 Ohm / 0.5W: 200 000 5225
SM/Transsonic_LC/1104/D © Elma GmbH & Co KG