Power quality monitoring equipment?

[cjard]

The office where I work has 6 banks of fluorescent tube lights on 6 switches (2 tubes per luminaire, 4 luminaires per bank, so 48 tubes/24 luminaires in total) that have developed a simultaneous flicker. Of late it has on occasions been so bad that the office briefly goes dark, and then the lights struggle to come back on. Other office equipment (monitors, PC power supplies) makes a faint noise, like when a poor electrical connection is evident (a popping/sparking/fizzing sound) at the same time the lights are flickering. We've reported it to maintenance, but are being fobbed off with crap like

them: "well, if one tube is on the way out, you'll get a flicker..."
us: "but every light in the office flickers at the same time"
them: "Yes, even if one tube in one luminaire is going out, it will upset all the other luminaires on all the other circuits"

They add insult to injury by saying that even though we rent the office space (and these luminaires came already fitted to the ceilings when we started renting the unit), electrical problems within the unit are our problem/responsibility to fix and because noone else has this problem, it's not their problem..

I'm convinced their "one of the light fittings or tubes or starters is broken and causing all these problems" story is a pail of horsecrap and it's a quality-of-power-supply problem that's external to the room. I'd like to know if there's something like an oscilloscope that I can plug in and take a recording of, or better still one that does its own data logging, that monitors the quality of the incoming power supply to the lighting/sockets - preferably without spending thousands..

Attached is a zipped up movie (sorry; movies can't be attached directly) of the lights doing their flicker (bit at the start, then a big drop near the end - it's hard to catch these things with a phone camera in the same way the eye sees them) - any comment on the "it's a bulb" claim?

 

[flameport]

Voltage dropping too low, perhaps due to defective connections, too much load elsewhere or similar. Do your neighbours have welders, X-ray machines or similar devices?
It certainly isn't a failed tube/bulb/starter.

Devices can be purchased or more likely rented - such as https://www.instruments4hire.co.uk/test-equipment/category-11-Power-Quality-Analysers/

 

[mikeyd]

I'd say from your description it's likely to be an external fault. Trouble is if you did have some sort of logger on it, where would you put it without "Maintenence" telling you it's still caused by the tube on it's way out? How often is it happening? I'd try to prove there isn't any possibility of it being internal and pass it back to them.
Leave 3 banks on and see if it happens, other 3 banks on, all PC's etc. shut down. If it's too intermittent to be practical in the daytime, get an IP camera and some software set to record on events and monitor at night/weekends (If I'm allowed to recommend, iSpyConnect is free/open source, other software is available)
As flameport has said, is it a shared building and if so do the neighbours notice anything?
Do all the symptoms come back to one sub-main or fuse board?
As usual, pictures would help, of the incoming supply.

 

[SimonH2]

them: "Yes, even if one tube in one luminaire is going out, it will upset all the other luminaires on all the other circuits"

They add insult to injury by saying that even though we rent the office space (and these luminaires came already fitted to the ceilings when we started renting the unit), electrical problems within the unit are our problem/responsibility to fix ...

That is normal in commercial leases - but it does very much depend on the terms of your lease.
Some "easy in-easy out" short term office rental makes your landlord responsible for maintenance. But normally, the tenant is responsible for maintenance of their space (that includes the windows as my ex employer was annoyed to be told) - and handing it back to the landlord in the same condition when they leave.

 

[cjard]

It's a shared block; local council run thing. Used to be a textile mill I think, now it's all partitioned up into office rooms. I don't know if there is an unlocked room or area I can go to to see the distribution boards, but I'll have a look around.. best I can recall, I used to work for a company in the block, who rented several office units. They had a heatwave one year and the boss brought in 6 large personal air con units (about the size of a small wheelie bin each) - plugging those in plus about 30 PCs, it only took one of the marketing girls in a different office unit (same floor) turning the kettle on and poof- no more electricity supply on that floor of that building (there are several mill buildings). I've a distinct memory of running down the road to B&Q to purchase an extension lead long enough to reach out of the window and down to our unit on the lower floor that still had power, in order to plug the server rack back in.. in true comedic fashion the UPS gave up a few seconds after we got the server room door open, and a few seconds before we'd reached the set of plugs powering the rack...

 

[sparkymarka]

Some UPS Units can monitor voltage high and lows , we had same issue at our office ,contacted DNO they left some logging equipment onsite and it turned out to be a poor joint in the road , been ok since ..

 

[SimonH2]

... in true comedic fashion the UPS gave up a few seconds after we got the server room door open, and a few seconds before we'd reached the set of plugs powering the rack...

I know that feeling. A few years ago I needed to shift our server room to a different supply while the electricians replaced a buring out switch in the meter room. Not having a spare breaker for the old Bill boards I thought I'd get everything but the L connected up on the alternative supply (20m of 16mm² T&E with a 63A commando socket on the end) and then quickly borrow the breaker from the normal supply while everything runs on batteries.
In the same comedic fashion, I'd just finished tightening the screw on the L terminal and about to switch on when things went eerily quiet

But stories like yours are common as a lot of these old buildings didn't have huge lecky supplies, and once you start loading up offices with computers and everything else then it's not hard to overload things. It's worse for many of our friends across the channel - in a previous job we had an office in Italy which regularly lost power if they didn't properly juggle use of the aircon with the kettle etc. It's common in several countries (Spain is another) to have capacity limited supplies (could be as low as 5A, and generally "pay more, get more") with an MCB to enforce the limit.