Voltage Discrepancy with APC UPS BV1000I-MST: 230V input & 206V output?

[GammaGlobulin]

Scenario (actual conditions, in fact):

 

a. I have three identical APC UPS units: BV1000I-MST

 

b. The voltage in this house is, as I just measured, 230 Volts.

 

c.  I measured the output voltage from all three UPS units:  range is from 206 to 207 volts AC

 

d.  So, why the discrepancy?

 

My only thought is that perhaps the volt meter I am using is not a True-RMS device?

 

Any thoughts?

 

Very strange, as usual.

 

Regards,

 

Gamma

 

 

https://www.se.com/th/en/product/BV1000I-MST/apc-easy-ups-1000va-floor-wall-mount-230v-4x-universal-outlets-avr/

 

 

 

 

 

[Crossy]

Are you measuring the output with the UPS disconnected from the mains?

 

It's not pure-sine so you could be correct with your meter thoughts.

 

https://www.apc.com/th/en/product/BV1000I-MST/apc-easy-ups-1000va-floor-wall-mount-230v-4x-universal-outlets-avr/

 

Either way what you are seeing is well within the normal operating range of most appliances particularly those with universal power supplies.

 

[GammaGlobulin]

Just now, Crossy said:

Are you measuring the output with the UPS disconnected from the mains?

 

No, I am not.

The UPS, all three units, is connected to the PEA grid at time of measurement.

 

Also, you can see that this design is not an ONLINE UPS.

Therefore, it seems strange that there is this voltage discrepancy, since it is my understanding that the UPS does not switch to battery until milliseconds after power outage....transfer time is about 6ms, and 10 ms, maximum...for this particular design.

 

 

[Crossy]

9 minutes ago, GammaGlobulin said:

 

No, I am not.

The UPS, all three units, is connected to the PEA grid at time of measurement.

 

Also, you can see that this design is not an ONLINE UPS.

Therefore, it seems strange that there is this voltage discrepancy, since it is my understanding that the UPS does not switch to battery until milliseconds after power outage....transfer time is about 6ms, and 10 ms, maximum...for this particular design.

 

 

 

OK, so you are actually measuring the output of the UPS whilst it's on mains "pass through".

 

I note that this unit has a built-in AVR which would explain how it's giving out a different voltage to what's going in.

 

What do you see when it's running on battery?

 

EDIT Do you have a load on the output when checking, try 200W or so.

[GammaGlobulin]

1 minute ago, Crossy said:

 

OK, so you are actually measuring the output of the UPS whilst it's on mains "pass through".

 

I note that this unit has a built-in AVR which would explain how it's giving out a different voltage to what's going in.

 

What do you see when it's running on battery?

 

I will not be able to test the voltage until the washing-machine technicians return with their volt meter.

I will test again, at that time, later in the week.

 

Also, I have looked at the specs for this unit, and you can see that there is no output voltage specified. Only a range for input voltage is stated.

https://www.se.com/th/en/product/BV1000I-MST/apc-easy-ups-1000va-floor-wall-mount-230v-4x-universal-outlets-avr/

 

In addition, after a power outage, and even though it seems that power has been restored by PEA, still one of the units will continue to beep 4-times, even though the other two units are usable.

 

Apparently, these units are quite sensitive to low power from the grid, or at least one of them is.

I also have two other APC UPS units which I am unable to use here due to the poor quality electric power being supplied, it seems.

 

 

 

[GammaGlobulin]

13 minutes ago, Crossy said:

 

OK, so you are actually measuring the output of the UPS whilst it's on mains "pass through".

 

I note that this unit has a built-in AVR which would explain how it's giving out a different voltage to what's going in.

 

What do you see when it's running on battery?

 

EDIT Do you have a load on the output when checking, try 200W or so.

 

I will test again, in a couple of days, when I have access to a "good" volt meter.

 

[Crossy]

Nip down to Lotus's or your favourite DIY place and get a cheap digital multimeter. even the cheapies are fine for comparison measurements.

 

Then you will be able to respond to our questions in a timely manner. 

 

How old are these units?

 

If your supply is 230V as you suggest there's no reason for your UPS to do anything unusual.

Unless, of course the "GammaGlobulin make odd things happen" field is active.

[GammaGlobulin]

2 hours ago, Crossy said:

Nip down to Lotus's or your favourite DIY place and get a cheap digital multimeter. even the cheapies are fine for comparison measurements.

 

Then you will be able to respond to our questions in a timely manner. 

 

How old are these units?

 

If your supply is 230V as you suggest there's no reason for your UPS to do anything unusual.

Unless, of course the "GammaGlobulin make odd things happen" field is active.

 

aa. Correct. I am at fault here, and responsible for any delays in getting to the bottom of this issue.

 

bb.  All three UPS units were purchased at the same time, within days of each other, about 30 days ago. Purchased from JIB near RAM Hospital.

 

cc.  The meter I choose must show voltage, and also show whether or not a line is properly grounded.   (Amperage reporting would also be nice, but not necessary.  The voltage here is so unstable that the multimeter is a must-have device.)

 

dd. In this case, I am reporting whatever I see/measure, and without resorting to poetic license.  I will not be able to make further measurements until the washing-machine man returns to fit a drainpipe and ground....

 

Until then...then....

 

[Crossy]

If they are that new, I'd be going back to JIB and having a moan.

 

[GammaGlobulin]

16 minutes ago, Crossy said:

If they are that new, I'd be going back to JIB and having a moan.

 

 

First, I must establish that the units are not performing as designed.

Today was the first time I had measured the output voltage.

I need to test more this week, and then contact JIB if warranted.