Voltage Optimisation Units

[Andy-1960]

Hi All,

Have come across a site today where the client has had a voltage optimisation unit fitted on his incoming mains supply.
The supply transformer is rated at 2MVA, and the voltage optimiser at 2250A (which appears to be undersized to me!)
Just wondering if anyone has come across these things and how it may affect the Zs values on the site?

 

[Pete999]

Hi All,

Have come across a site today where the client has had a voltage optimisation unit fitted on his incoming mains supply.
The supply transformer is rated at 2MVA, and the voltage optimiser at 2250A (which appears to be undersized to me!)
Just wondering if anyone has come across these things and how it may affect the Zs values on the site?

Hi All,

Have come across a site today where the client has had a voltage optimisation unit fitted on his incoming mains supply.
The supply transformer is rated at 2MVA, and the voltage optimiser at 2250A (which appears to be undersized to me!)
Just wondering if anyone has come across these things and how it may affect the Zs values on the site?

Voltage Stabilizers Yes, optimizer no experience.

 

[Andy-1960]

Voltage Stabilizers Yes, optimizer no experience.

Just for you Pete, so you can see what they look like.

 

[Bobster]

Does it just monitor output voltage from the TX and adjust tappings automatically when required?

 

[suffolkspark]

They shouldnt have every circuit running through them, big clive did a tear down of one of the pieces of sh** on youtube, have a gander

 

[Bobster]

Save up to 19% on your electricity bills by installing a three phase voltage optimiser at your business. Thanks to harmonisation across Europe much of our equipment works most efficiently at 220v. In the UK electricity is supplied at an average of 242v. Anything over this voltage is wasting energy – energy you are paying for.

From their website. What utter sh!t.

 

[Andy-1960]

From their website. What utter sh!t.

I totally agree!

 

[marconi]

You might want to consider the effect of voltage imbalance on 3 phase motors. Does the client have a large number of such motors running much of the time? The purpose of the voltage optimiser (regulator/stabiliser would be more descriptive of its purpose perhaps) would be to reduce the percent imbalance. The device is producing these phase voltage outputs 224.1V, 225.6V, 225.8V while supplying phase currents of 1208A, 1183A, 1127A. I think that is pretty impressive.

See: The Basics of Voltage Imbalance - https://www.ecmweb.com/content/basics-voltage-imbalance

 

[Bobster]

The improvement in large motors running like that in a factory would be wholly negated by the reduction of the voltage and the extra heat generated by the motors.

There are far better ways of improving motor efficiency and power draw than fitting one of these units.

Not to mention I have yet to see a 400/220V motor. Usually see 400/230.

 

[marconi]

There are far better ways of improving motor efficiency and power draw than fitting one of these units.

I'd be interested to hear a little more about these better (cost-effective) ways. Are you suggesting a device for each motor?

 

[Bobster]

VFD control for motors would be better for efficiency.

Then you need to look at cost savings vs initial outlay for the VFDs.

Biggest savings by far are motors used on fans, that control the air flow with dampers. If you only need the fan running at 80% speed, you'll achieve on average a 40% reduction in energy.

If you're clever with their set up, you can also use regenerative functions on slowing the motor down, to back feed into a DC bus used to power other motors. Effectively turning the motors on site into generators. Otherwise slowing a motor down is just wasting energy.

Decent site power factor correction is a must for factory with large motor installs. Although don't go down the route of fitting local power factor correction units to motors. That opens up a whole other can of worms if they are not integrated properly.

 

[marconi]

Rob - thank you.

As you may gather, I think there is more to VO (as I have said ought to be VR/VS and there are some snake oil marketing ploys targeted at the gullible and ignorant which should be taken down ) than first meets the casual eye.

I don't believe in a linear world: I think it is in the reality of inherent non-linearity in machines lies the way some energy savings are made by VO/VR/VS - but that would be too difficult to explain to ordinary business folk hence the snake oil.

So(eg), at 220V rather than 240V it may take 3% say longer to do the same repeated mechanical task (eg move something from a to b) but uses 0.5 % less energy.

Similarly, a store has say 50 fluorescent lights burning 8am to 5pm. What is the cheapest way to dim them? Lower the supply voltage. Do stores get many complaints about dim lighting - I guess not. And the tubes might last say a few months longer.

That repetitive saving and a number of others consequential to having a voltage reduction (dimmer lighting without having to change all the tubes and fittings or fitting swanky remotely controlled lighting) might be worth pocketing - all for the one off fixed cost of fitting a VO ie: a one-off cost effective expenditure. This is why I think the business case satisfies bottom-line businesses in certain situations

I am not saying I am infallibly right on this. But I do think there is economic merit in it in specific cases so it should not be summarily written off. (Yes I get that closed loop thermostatically controlled heaters will use the same energy but to my mind they are linear.)

PS: I do have a VR/VS in my home.

 

[Bobster]

And has the unit paid for itself in energy savings yet?

 

[marconi]

And has the unit paid for itself in energy savings yet?

Yes. I also think of all those transformers and motors - the door bell, my wife's air bed, the medical fridge fan, the wifi printer, the bt router, the sky box, two electric reclining chairs...plugged in using less quiescent power.

And not only energy savings - I rarely have to change a halogen lamp, led lamp, cfl lamp and we have around 30 burning each night.

 

[Bobster]

Yes. I also think of all those transformers and motors - the door bell, my wife's air bed, the medical fridge fan, the wifi printer, the bt router, the sky box, two electric reclining chairs...plugged in using less quiescent power.

I'm sorry, I just don't see it. Unless you payed pennies for the unit.