Determine UPS KVA

Hi guys,

I am going to purchase an UPS to power a Siemens touch panel and plc S7-200. I would like to know how and what varible do i need to calculate the power consumption? Pls advice. Thank you.

Hi WHtrader,

On the labels of the units is mentioned what power cunsumption they have. That in combination with the time you want to have them up and running durring a power cut should be more then sufficient enough for a supplier to calculate the amount of power needed.

A more precise indication of the power consumtion is when you measure the consumtion in real time logging the maximums over a period of one or two day's during normal operation.

Keep in mind that the surrounding temperatur for a ups is far less then for a cpu and/or panel. When the temperature is to high for the ups the backup time is decreased rapidly !!

Thats for my 2 cents, good luck

Thanks for your reply JvdV. I believe the location of the UPS will be hot.

Read this:
http://www.plctalk.net/qanda/showthread.php?t=25484&highlight=UPS

Here is a type of table you will be looking at.

This happens to be from Phoenix Contact for 24VDC UPS. I think their temperature ratings are much much better than you would get from an "office supply" ups.



[font=arial,helvetica,sans-serif]A = QUINT-BUFFER/24DC/20 (P/N 2866213) (No battery required)
B = QUINT-DC-UPS/24DC/10 (P/N 2866226) (Internal 1.3AH battery included)
C = QUINT-DC-UPS/24DC/20 (P/N 2866239) and QUINT-BAT/24DC/3.4AH (P/N 2866349)
D = QUINT-DC-UPS/24DC/20 (P/N 2866239) and QUINT-BAT/24DC/7.2AH (P/N 2866352)
E = QUINT-DC-UPS/24DC/20 (P/N 2866239) and QUINT-BAT/24DC/12AH (P/N 2866365)
F = QUINT-DC-UPS/24DC/40 (P/N 2866242) and QUINT-BAT/24DC/3.4AH (P/N 2866349)
G = QUINT-DC-UPS/24DC/40 (P/N 2866242) and QUINT-BAT/24DC/7.2AH (P/N 2866352)
H = QUINT-DC-UPS/24DC/40 (P/N 2866242) and QUINT-BAT/24DC/12AH (P/N 2866365)[/font]

<Disclaimer> I work for a Phoenix Contact Distributor.

Mickey said:

Read this:
http://www.plctalk.net/qanda/showthread.php?t=254:beerchug:84&highlight=UPS

Click to expand...

Thanks for the link.

Here is a type of table you will be looking at.

This happens to be from Phoenix Contact for 24VDC UPS. I think their temperature ratings are much much better than you would get from an "office supply" ups.

Click to expand...

Ya thanks for the info. I asked the supplier and they point me to their website with a calculator.