Malfunction In The Inverter Or Single Tank - Siemens MOBILETT Plus Service Instructions Manual

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Malfunction in the inverter or single tank

The following procedure will help you to determine whether the problem is caused by the
inverter or the single tank.
The current flow between the inverter and the single tank must be approx. symmet-
rical. If this is not the case, the inverter is defective.
Measure the resistance between K63/POS and K64/1 or K64/2 or K63/NEG and K64/1 or
K64/2. The value must be larger than 0.5 Mohm. If the value is less than 100 ohms, the
inverter is defective (transistors in the modules are bad).
Measuring the falling edge of the high voltage (in the measurement point HT on D1 board)
Long falling edge (approx. 2 ms)
(Separate current transformer between
Asymmetrical inverter current e.g.,
one-sided or one half-wave significantly
lower (diff. >50%), or no current can be
measured
Inverter or cable
K64 defective
NOTE
MOBILETT Plus/ Plus E
HT and single tank error diagnosis
Measuring the inverter current
inverter and single tank)
The inverter current is always measured using a separate current
transformer between the inverter and single tank. The procedure
is described in the training video.
Short falling edge (approx, 50µs)
Symmetrical current and current
>300A, See figs, 3 and 4.
Single tank or
cable K64
defective
SPR8-215.898.02
Rev. 01 01.02
(Tube arcing)
Single tank or
cable K64
defective
Page 2 of 12 Siemens-Elema AB
SPS-UD
6
Solna, Sweden