Sine Waves and Efficiency of different UPSs


#1

All the sine waves have been taken during running a PAK pedestal fan 150W. Almost all (excluding last 2) UPS are "Modified Square Wave" type. When no load, wave form is ok and when load is connected, wave form is distorted.

So it has been proved that the best available UPS in affordable price in local market is Systek. After these tests, i bought Systek ECS-202 and replaced with my old daisi UPS.

For running 4fans and one light, old daisi UPS was drawn 40A from a 12V battery

After replacement and with same load, Systek draws 15.5A @ 24V (and thus 31A at 12V). So the back up time increased by almost 1hour. I found excellent features in Systek, a good charging system and under-over volatge protection of battery. Internal filters made the output wave form smooth even in fan load for which the wave forms of other UPSs are distorted.

The efficiency of above UPSs will be informed latter as the work has not been completed yet. But according to initial tests, Systek is also better in efficiency because of a "near to sine wave" even in inductive load condition.


#2

Hmm. HOMAGE matrix is also giving good stepped sine wave current. Last time when I checked vision model, it's output was little spiky but this newer one is better.

What is the cost price of Systek ECS-202?


#3

Nice info - waiting for efficiency results of Systek.

BTW: The Siemens waveform is near to perfect.


#4

Systek ECS-202 Rs.15,000. 24V

Systek ECS-101 Rs.12,500. 12V


#5

Awesome...was waiting for such analysis for quite some time...Waiting for efficiency results. And Siemens one is really great...


#6

VERY useful thread and tests! Thank you for that.. finally someone put their oscilloscopes to good use and public benefit :P

Siemens one gives a WOW waveform!! Price is also wow though :-/

How is the charger of Systek?


#7

are these Siemens UPS's available in Pakistan, and up to what VA?


#8

signode brother plz check deutsche ups waveform they are claiming pure sine wave as well


#9

Waiting for efficiency tests.....

@Signode. Please clarify if you have some conflict of interest in this case (i mean any association with systec?)


#10

[quote=“generaluser, post:9, topic:17125”]

Waiting for efficiency tests…

@Signode. Please clarify if you have some conflict of interest in this case (i mean any association with systec?)

[/quote]

For Siemens UPS, please contact with Siemens Pakistan as they supply after a customer order.

I work in a company/factory where, when load shedding/power flickering strated, we asked to our commercial department and they bought diferent UPSs for us time by time for our sensitive electronic items such PLCs and HMI PCs. But even after installation of UPSs, we faced problem of PLC program corrupt or PC failed which forced us to deeply study the UPS as before that there was no any study from our side about UPS. Moreover, asking of people “which UPS should we select” also forced us to deeply study the UPSs. Me too have daisi UPS in my home which now i am going to replace with Systek.

So this time we have all those UPSs in our plant which wave forms i tested excluding Systek and Homage. We saw Systek UPS in Lahore Expo Center and we intrested in becasue of good features. So i got one peice for demonstration. For Homage, i got it from my one friend just for wave form tests. Now as we have arranged spacial instruments for measurment of non-sinusiodal out put of such UPSs, i will present with efficiency report.


#11

[quote=“signode, post:10, topic:17125”]

For Siemens UPS, please contact with Siemens Pakistan as they supply after a customer order.

I work in a company/factory where, when load shedding/power flickering strated, we asked to our commercial department and they bought diferent UPSs for us time by time for our sensitive electronic items such PLCs and HMI PCs. But even after installation of UPSs, we faced problem of PLC program corrupt or PC failed which forced us to deeply study the UPS as before that there was no any study from our side about UPS. Moreover, asking of people “which UPS should we select” also forced us to deeply study the UPSs. Me too have daisi UPS in my home which now i am going to replace with Systek.

So this time we have all those UPSs in our plant which wave forms i tested excluding Systek and Homage. We saw Systek UPS in Lahore Expo Center and we intrested in becasue of good features. So i got one peice for demonstration. For Homage, i got it from my one friend just for wave form tests. Now as we have arranged spacial instruments for measurment of non-sinusiodal out put of such UPSs, i will present with efficiency report.

[/quote]

we are waiting for the efficiency part, it would be really great if you could somehow get aurora and mercury UPSes.

My own impression of systec was that they make probably the best of all the LOCAL_MADE UPSes


#12

Nice info man.. what do you guys think about homage?am not getting this diagram :D is it good to go?


#13

[quote=“koder, post:12, topic:17125”]

Nice info man… what do you guys think about homage?am not getting this diagram :D is it good to go?

[/quote]

Its not Good to go instead its OKAY to go…the waveform is somewhat in a proper cycle compared to some others…


#14

Switch-over time of Systek claimed in their brochure is pretty damn good! Just 2ms.. Homage I've read here in other threads has high switch-over time, so can cause PC to shutdown, or shutdown under load!

Better get Systek, judging from these results and their claims in brochure.. But only before getting a proof of these claims or more positive reviews.


#15

^ Is there any evidence of this switchover time? How about putting the full rated load on one of their UPS and checking the switchover time? :)

On that note, how about greater than 75-80% load on the UPS and the resultant o/p AC waveform?


#16

Dear friends,

Efficiency test for such kind of non-sinusoidal output is not an easy job. I have an initial report but i want to make it 100% ok. Four different energy meters have different results because of distorted waveforms. I am making discussions with different engineers how to measure the energy in such case. So please bear with me as report will be finalized in next week.

Dear Asad,

This is a good idea to put a full load on UPS and then switch-off the wapda to test the switch-over time. I have Laptop in my home. So for testing of switch-over time, i need to arrange a desktop PC from somewhere.


#17

[quote=“signode, post:16, topic:17125”]

Efficiency test for such kind of non-sinusoidal output is not an easy job. I have an initial report but i want to make it 100% ok. Four different energy meters have different results because of distorted waveforms. I am making discussions with different engineers how to measure the energy in such case.
[/quote]

You need to use True RMS measuring devices (multimeters or power meters) to accurately measure non-sinusoidal waveforms.

Fluke 87 is just one example of such type of multimeter.


#18

[quote=“Asad, post:15, topic:17125”]

^ Is there any evidence of this switchover time? How about putting the full rated load on one of their UPS and checking the switchover time? :)

On that note, how about greater than 75-80% load on the UPS and the resultant o/p AC waveform?

[/quote]

Nah, no evidence at all… just mentioning their ‘claim’ in brochure… It might not be true under 80%+ load… Hopefully signode can test this for us? :P


#19

[quote=", post:17, topic:17125"]

You need to use True RMS measuring devices (multimeters or power meters) to accurately measure non-sinusoidal waveforms.

Fluke 87 is just one example of such type of multimeter.

[/quote]

Dear Ijaz,

We have very good quality instruments (which are very costly) as we need to trouble shoot in machines but never time faced such case. I measured the input and output of UPS by using 8 measuring instruments but now i am very close to make a final report.


#20

I appreciate your work and contribution to this forum but there is a difference between good quality and required functionality.

The required functionality in this case is to be able to measure true RMS.

Keep up your work and post efficiency results.