great deal on Tripp lite SMART1000LCD, how good is this UPS

B

blue_heart71

Limp Gawd
Joined
Dec 21, 2003
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was at Costco today and found this Tripp lite UPS @ $99+tax

i am intending to buy 5-6 of them for me and for my friends, each to be used on AMD64 desktop pc with 2gb ram and quadro 3400 gc and crt monitors.

the deal is killer and i liked the specifications.

any drawback?
 
1000VA / 500 watt power handling ability supports a variety of sensitive computer, home theater and other equipment
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It is only 500W!

Sam's Club has discontinued APC Back Pro 1100's for $125.
These use RS232 instead of USB, but they were $454 units only 2yrs ago.

I have 4. ;)
 
i think 500w is fair enough for single not loaded desktop pc, also this is new model not discontinued
 
I wanted to bump this to see if anyone else has additional impressions of this UPS. I was considering going for overkill and getting the APC RS1500, but according to the "selector" applets on tripplite.com and apc.com, I only really need ~500W max for 10-15 minutes of battery time, even factoring in 30-35% growth potential.

The APC will end up being $190, the Tripp Lite will be $110. All things considered I'd rather turn that $80 into more RAM (or something) or, god forbid, a credit card payment. BUT I want to protect my new rig and in my mind it makes sense to give myself a lot of room for growth should I eventually upgrade my rig. I can also pick up the APC RS1200 for $162 (each at Office Depot).

One other note, I don't beleive the Tripp Lite battery can be replaced, and if it can, it's definitely not hot-swappable. There is no replacement battery listed on their site. Perhaps this would affect your opinion. Then again if I get it at Costco I can return it anytime I want an upgrade. Hmm, that maybe seals it. Thoughts?

TIA.
 
blue_heart71 said:
i think 500w is fair enough for single not loaded desktop pc, also this is new model not discontinued
Click to expand...

that might depend

Power Supply System Integration Part 2: Battery Backup @ Power Electronics Technology
UPS Nonlinear Loads

Most end users are oblivious to the problems encountered when an online UPS interacts with nonlinear load, such as a switchmode power supply. Fig. 3, on page 42, illustrates the interface between an online UPS and a switchmode power supply. The switchmode supply within the host system consumes its current in high amplitude pulses, and as a result overloads the UPS, distorts its output and degrades in performance. This isn't the case if the SMPS has power factor correction (PFC); and in the United States most SMPS don't have PFC.

Repeated measurements under practical conditions show that in non-PFC SMPS, the current peak to rms ratio reaches a crest factor in the range of 2.5 to 3.5. This high crest factor imposes a difficult load for the UPS.

Manufacturers specify UPS capacity in volt-amperes, and set the UPS current limit with resistive loading. This affects the user in two ways: first, the actual power (in watts) that the online UPS can deliver is 75% to 80% of its VA rating. Second, the UPS cannot support a nonlinear load like a SMPS to full power capacity. In fact, it can support an SMPS only rated to 30% to 40% of its capacity. A 1kVA online UPS will only be suitable for backing up a system energized by a 300W to 400W (non-PFC) switchmode power supply. Attempts to draw higher power by the SMPS will severely distort the output of the UPS and may result in shutdown. Some UPSs support nonlinear loads to various degrees, but the above rule is safe to use as a guideline.

The whole idea of generating a high-purity sinewave within the UPS, and then rectifying it within the SMPS is wasteful. A UPS may be deployed to run non-electronic loads, such as lights or motors. However, this is a minor portion of the market for online UPS. Many applications back up computers and telecom devices, as well as instrumentation systems used for critical applications. In all of these applications, the immediate load for the UPS is the SMPS within the systems. Peak current and inrush current are associated with this load at startup. This current of 40A to 80A per SMPS will cause the UPS to shutdown due to overloading, or the UPS must transfer the load to utility to draw its inrush.
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I "upgraded" the importance of active PFC in purchasing a power supply, as it does seem to have a great deal to do with not abusing and effectively employing the capacity of an online UPS (and by extention Id assume a line interactive UPS \ SPS when its on batteries, a far more common UPS scheme) and the type addressed here, the main difference being that an online is always using the inverter and the interactive only when "on batteries"
 
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