Checking The Secondary Diode - Fronius Transpocket 1500 Erdstrom Serviceanleitung, Ersatzteilliste

Checking the
transistor
module
(continued)
Fig.18
Checking the - Open the housing (see the section headed: "Opening the housing")
secondary diode
Fig.19
Fig.20
(7)
0.2 - 0.7 V
Diode path: "Rectifier AC
Warning! An electric shock can be fatal. Before beginning with the test
procedure, discharge all the electrolytic capacitors.
(2)
Detach transformer cables from the secondary
diode
0.15 V - 0.4 V
Measuring the diode path on the secondary diode
- Detach both transformer cables from
the secondary diode:
- undo the M4x20 (TX20) screws (2)
- remove the screws (2) with cup
Important! The secondary diode has two
parallel diode paths.
- Measure the diode paths in the
conducting direction (Fig 20), with a
diode testing device (e.g. multimeter
with diode testing function)
- Measure the diode paths in the non-
conducting direction as well
- Replace the secondary diode if the
measurements in the conducting
direction show that:
- the measured voltage drop is
- a short-circuit or high-resistance
- Also replace the secondary diode if a
short-circuit or low-resistance
continuity is measured in the non-
conducting direction
48
with cup springs (Fig.19)
springs
significantly outside the specified
tolerance ranges, or if:
continuity is measured