W
Wild_Bill
Guest
I wasn't able to find any archived info regarding repair of this somewhat
sophisticated, high current PSU. This is the 180W version of this ADP series
of SMPSs.
The process of disassembly wasn't trivial.. Loctite has been used on
numerous internal screws during assembly, but heating them with an iron can
loosen the threadlocker well enough to remove the screws without stripping
out the
shallow #1 phillips recesses.
The top of the single-sided 4"x6.5" board looks straighforward enough that
it appears to be repairable, however, the bottom/foil side has a lot of
surface
mount circuitry (roughly half of the bottom side) which causes me to think
that repairing these supplies isn't simple.
The in-circuit ESR of the few (only 5) electrolytics appear to be good. Two
of them are rated 125C, the others are 105C.
The single 12V output is just 2 leads to the 6-contact plug at the end of a
shielded, 12 gage cord (pins 1, 2, 3 Gnd, and 4, 5, 6 positive).
The symptom is similar to the tick-tick failed startup of other SMPS, where
the output occurs in brief pulses at about 5 second intervals.
The load used is a #9004 halogen automotive hi/lo beam headlamp 45W 3.75A
and 65W 5.4A.
No load - the LED pulses on at about 5 second intervals, while a DMM display
wanders erratically between 3V and 11V.
Medium load - ~45W same pulses as above, and a brighter pulse after AC power
is
shut off.
High load - ~65W same as above.
Large load - ~110W No pulses during power on or after AC is shut off.
I haven't been doing service repairs for years, but I have an isolation
transformer (PR57) and safe troubleshooting habits, but the large number of
surface mount components on the board have me leaning toward an unlikely
repair, unless someone would be willing to offer some helpful advice.
Other observations:
As an aside comment, there is a surface mount IC where 2 of the pins have
been eliminated/omitted (not cut off), apparently to save money in
fabrication.. I've never seen this before.
The board manufacturer is Delta. For use with Information Technology
equipment.
ADP-180AB Made in China DCWP CM-2, CC: BB Rev 03.
Input: 100-240VAC 2500mA. The AC line fuse is 4A 250V.
Output: 12 VDC 15000mA.
The plastic case is unvented. The thin sheetmetal "shields" are secured to
the heatsinks with heatsink grease to increase the surface area of the
heatsinks.
--
Cheers,
WB
..............
sophisticated, high current PSU. This is the 180W version of this ADP series
of SMPSs.
The process of disassembly wasn't trivial.. Loctite has been used on
numerous internal screws during assembly, but heating them with an iron can
loosen the threadlocker well enough to remove the screws without stripping
out the
shallow #1 phillips recesses.
The top of the single-sided 4"x6.5" board looks straighforward enough that
it appears to be repairable, however, the bottom/foil side has a lot of
surface
mount circuitry (roughly half of the bottom side) which causes me to think
that repairing these supplies isn't simple.
The in-circuit ESR of the few (only 5) electrolytics appear to be good. Two
of them are rated 125C, the others are 105C.
The single 12V output is just 2 leads to the 6-contact plug at the end of a
shielded, 12 gage cord (pins 1, 2, 3 Gnd, and 4, 5, 6 positive).
The symptom is similar to the tick-tick failed startup of other SMPS, where
the output occurs in brief pulses at about 5 second intervals.
The load used is a #9004 halogen automotive hi/lo beam headlamp 45W 3.75A
and 65W 5.4A.
No load - the LED pulses on at about 5 second intervals, while a DMM display
wanders erratically between 3V and 11V.
Medium load - ~45W same pulses as above, and a brighter pulse after AC power
is
shut off.
High load - ~65W same as above.
Large load - ~110W No pulses during power on or after AC is shut off.
I haven't been doing service repairs for years, but I have an isolation
transformer (PR57) and safe troubleshooting habits, but the large number of
surface mount components on the board have me leaning toward an unlikely
repair, unless someone would be willing to offer some helpful advice.
Other observations:
As an aside comment, there is a surface mount IC where 2 of the pins have
been eliminated/omitted (not cut off), apparently to save money in
fabrication.. I've never seen this before.
The board manufacturer is Delta. For use with Information Technology
equipment.
ADP-180AB Made in China DCWP CM-2, CC: BB Rev 03.
Input: 100-240VAC 2500mA. The AC line fuse is 4A 250V.
Output: 12 VDC 15000mA.
The plastic case is unvented. The thin sheetmetal "shields" are secured to
the heatsinks with heatsink grease to increase the surface area of the
heatsinks.
--
Cheers,
WB
..............