APC Back-UPS RS 1100VA 230V Surge Protection

[Anonymous user]

Hi guys,

I'm kinda new here, and I know I have a lot to learn about UPSes. I'm interested in getting this one:
http://www.apc.com/resource/include/techspec_index.cfm?base_sku=BR1100CI&tab=models
APC Back-UPS RS 1100VA 230V

I just noticed though that the Surge Protection is kinda low compared to other UPSes of the same line. The specification lists 180 joules, where as other models typically have 320 joules. As the ratings are already quite low compared to a dedicated surge protector, what kind of issues would I face with having such a low surge protection rating?

One more thing, upon checking the pdf document for the specific model found here:
http://www.apcmedia.com/salestools/ASTE-6Z7VBY_R1_EN.pdf

I states that the AC Surge Protection is 440 joules. So which one is correct? Got kinda confused here. :S

Thanks,
Ken

[Anonymous user]

Thanks for the reply. That was helpful.

As for my other question, which is the correct rating though? Is it the 180 Joules listed on the page or the 440 Joules listed on the pdf file?

[BillP]

440 joules is the correct number as far as i can tell.

[BillP]

[take a look at this link where i gave an explanation of the ratings here|http://forums.apc.com/spaces/8/data-center-facility-3-phase-ups/forums/general/2243/questions-about-...]

also, you might see the term "eP Joules" thrown around..

eP Joules vs Joules:

APC uses the eP Joule Rating because we do not simply 'absorb' the surge like some other surge products might. Our products are designed to redirect the surge back to ground instead of absorbing it and incorporate a let through voltage, which is the maximum transient voltage the attached equipment will be subjected to above the normal RMS voltage. Any remaining voltage is redirected to ground.

I believe the reason we even list the eP rating is for comparison with our competitors products. If we just listed the standard Joule rating, it would in most cases be lower than the competitors, because we aren't relying on absorbing the impact with a MOV, we're redirecting excessive voltage away from your equipment and safely back to ground.

From my understanding, we come up with the eP Joule rating by performing real world tests with both our equipment and the competitors. Based on these results, we can see how many Joules of absorbtion our units are equivalent to.

all surge products are certified and will provide adequate protection per UL ratings, etc

hope this helps

[Anonymous user · Accepted solution]

Thanks for the all the help. 🙂