I have a customer who has a 12 yr old TOP CLASS 1800VA sinewave
inverter manufactured by ASP AG of Switzerland. The inverter died when
a pair of mice decided to set up home inside the case. Clever devils -
they waited till the fan was stationary and climbed in between the fan
blades - the fan was never fitted with a grille. One of the mice
committed suicide by climbing along the mosfet mounting rail which
bolts to the heatsink and his bodily fluids caused one bank of 8
mosfets to emit smoke and take out some smd components in the driver
stage. The local repair agents for ASP AG (about 4000km from me) don't
do board level repairs but will simply replace the whole board at a
cost of around $600, far more than my customer is prepared to pay for
such an old unit. He is prepared to spend a few hundred $ if it can be
repaired for backup service.

Unfortunately, ASP AG carefully grind off all identification marks on
the IC's on the PCB, which makes it very difficult to work out
replacements. I can understand why they do it but when they won't
supply repairers with circuit details it is a problem. I am wondering
if there is anyone out there who may be in possession of schematics or
service info for the ASP AG TOP CLASS series inverters and is prepared
to help me out. From a look at their website there appears to be
little change in the current PCB design and layout from the version I
am repairing.

Not to worry...

I have fixed it now - 8 mosfets, 2 sot23 transistors, 1 sot23 zener, 2
melf 10 ohm resistors. Luckily no gate driver IC's were faulty. I
later learned from ASP-AG the gate driver IC's are Power Integrations
INT200 and INT201 which are now obsolete.


On Thu, 11 Jan 2007 07:48:57 GMT, Ross Herbert
wrote:

I have a customer who has a 12 yr old TOP CLASS 1800VA sinewave
inverter manufactured by ASP AG of Switzerland. The inverter died when
a pair of mice decided to set up home inside the case. Clever devils -
they waited till the fan was stationary and climbed in between the fan
blades - the fan was never fitted with a grille. One of the mice
committed suicide by climbing along the mosfet mounting rail which
bolts to the heatsink and his bodily fluids caused one bank of 8
mosfets to emit smoke and take out some smd components in the driver
stage. The local repair agents for ASP AG (about 4000km from me) don't
do board level repairs but will simply replace the whole board at a
cost of around $600, far more than my customer is prepared to pay for
such an old unit. He is prepared to spend a few hundred $ if it can be
repaired for backup service.

Unfortunately, ASP AG carefully grind off all identification marks on
the IC's on the PCB, which makes it very difficult to work out
replacements. I can understand why they do it but when they won't
supply repairers with circuit details it is a problem. I am wondering
if there is anyone out there who may be in possession of schematics or
service info for the ASP AG TOP CLASS series inverters and is prepared
to help me out. From a look at their website there appears to be
little change in the current PCB design and layout from the version I
am repairing.