Reversed Polarity of the Output (APC UPS BR1100CL)

[Anonymous user]

Hi,

  I am currently in Thailand and I have been an owner of an APC UPS for a few months.  Recently, I used a neon-lamp-type tester and found that the polarity of the UPS outputs was reversed according to this diagram.  (The tester lit up when inserting into the neutral connector and remained unlit when inserting into the hot connector.)

http://tbn0.google.com/images?q=tbn:Q__cH8wcTB8e4M:http://www.tangible-technology.com/power/p2/7_out...

This reversed polarity occurred at all UPS outlets and I tested this while the UPS was connected to the wall outlet. I did not test this while the UPS was running on a battery.

I initially thought that my UPS was faulty and therefore, I called the APC customer service in Thailand about this issue.  Surprisingly, they told me that the UPS that are distributed in Asia are designed this way.  However, they were not able to give me a satisfactory explanation of why such decision was made.  Therefore, I am writing to inquire whether it is normal that the polarity of the UPS output is reversed.  Also, I would appreciate if you could provide me with some explanations regarding the design decision.

Regards,

Nirand Pisutha-Arnond

Product details (from the bottom panel)

APC UPS Model: BR1100CL, BR1100CL-RS, BR1100CL-AS, BR1100CL-IN

Input: 230 V~, 6A, 50/60 Hz

Output: 230V~, 50/60 Hz, 1100 VA, 660 W

[Anonymous user]

Power in Thailand (for all new construction at least) is governed by standard:

TIS 166-2549 (2006) Thai Industrial Standard for PLUGS AND SOCKET-OUTLETS FOR HOUSEHOLD AND SIMILAR PURPOSES : PLUGS AND SOCKET-OUTLETS WITH RATED VOLTAGE NOT EXCEEDING 250 V

https://law.resource.org/pub/th/ibr/th.cs.166.e.2549.pdf

The outlet you put a picture up for is not included in this standard that I can see.When I googled your model # the rear panel outlets looked like IEC C13's  to me so I'm a bit confused.

Hope this helps a bit.

[Anonymous user · Accepted solution]

Dear Battman,

  Thank you very much for your quick reply.  You are correct that the real-panel outlets are IEC-C13 type.  I think the reason for this type of connector is that most computers in Thailand use power supplies that have this connector.  Most electrical appliances do not have this connector, however.

  I think I will just continue to use this unit.  Again, I am still baffled at the fact that the polarity of the output is reversed.  (From the back panel, this unit was made in Philippines.  Maybe they have the opposite way of wiring hot and neutral connectors.)

Sincerely,

Nirand Pisutha-Arnond