SMT2200RM2U is it really true sinewave?

[whoolly_apc]

This was originally posted on APC forums on 5/31/2016

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The site says

• Pure sine wave output on battery
  Simulates utility power to provide the highest degree of compatibility for active PFC (power factor corrected) servers and sensitive electronics.

However, I have a device (StorSimple SAN) that is hooked up to 2 SMT2200RM2U units for redundant power.

Everytime we get a power flicker, the device has a controller failure.

When I had MS look at the log files, they state that it is because of power issue, like a 0.6 sec power loss.

So, the UPS isn't providing true sine wave power continuity from the sounds of it.

Anyone else have this problem? Any way to resolve, before I have to try to replace these with a different manufacturers units.

I have always preferred APC equipment, but I can't put my device in production if it can't stand a half second power flicker.

[prince213_apc]

This was originally posted on APC forums on 5/31/2016

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If your device demands sinewave then its always preferred to get Online UPS. Smart terminology by APC is just another marketing gimmick, its actually the line interactive UPS. Online UPS uses double conversion to powerup the load using both incoming power and battery power always and avoids the need of step and step down of voltage and gives clean power always. If you compare the quality of power output, Online UPS of any brand is far better than Smart UPS.

[BillP · Accepted solution]

This reply was originally posted by Bill on APC forums on 6/1/2016

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Hi,

A Smart-UPS provides true / pure sine wave however the topology of the UPS is line interactive so when the UPS switches from AC to battery output there is a minimal delay. The delay is based on the UPS sensitivity setting

High Sensitivity Mode
In the event of any type of voltage disturbance, the UPS will transfer to battery power and watch the AC line until it can transfer back to line. The transfer time in this mode depends on how far the line voltage deviates from the sine wave reference. It is generally 2-4 milliseconds.

Medium Sensitivity Mode
In the event of a RMS voltage-out-of-tolerance(High/Low/No) and RMS-rate-of-change disturbances(dv/dt) in the line voltage, the UPS will transfer to battery power and watch the AC line until it can transfer back to line. In this mode the transfer times are longer but still within acceptable limits to insure the continuity of a computer's operation. They are generally 6-8 milliseconds.

Low Sensitivity Mode
In the event of a RMS voltage-out-of-tolerance disturbances(High/Low/No) in the line voltage, the UPS will transfer to battery power and watch the AC line until it can transfer back to line. In this mode the transfer times are longer but still within acceptable limits to insure the continuity of a computer's operation. They are generally 8-10 milliseconds.

First you should verify the UPS is set for high sensitivity and if not switch to high sensitivity and test the equipment.

Most computer system run perfectly fine with any of these preset delays however some systems do not. If your systems cannot handle the delay when set to high sensitivity you will need to replace the UPS with an on-line topology model UPS. The SURTA2200RMXL2U is the on-line topology equivalent to the SMT2200RM2U