Wetroom Store - Network Wetroom Suppliers
This official sponsor may provide discounts for members

Discuss Practicality of 400 volt equipment in the Electrical Forum area at ElectriciansForums.net

uHeat Banner - Forum Discount Available
This official sponsor may provide discounts for members
Aico 3000
C

Cookie

-
  • Thread Starter Thread Starter
  • #26
A 400v element is inside it along with 400v controller

We manufacture it for the Scandinavian market
These heaters are these start of something great! Do you have pictures of the internals by chance? What electronic components (rating/type) you use on the circuit board? The tracks on the board? I'm assuming its directly across the mains.
 
J

Julie.

Esteemed
Arms
6 phase is actually more efficent, but I've read that its not worth the extra complexity.

If we were to mass produce 400 volt consumer products, would it be more expensive than 230 volt consumer was my primary questions- though its not really confined to that only. Anything and everything is open to discussion around this subject.




True. The only thing that will need to be re-designed are single pole switches.
Not really, the whole wiring systems are designed around 230/400v rather than 400v

Switches and breakers are the most obvious, but my whole point is there are and have been other voltages, but the balance of advantages/disadvantages appears to work out around the 230/400v mark which is why it has ended up being the voltage range of choice.

It may be that as technology advances, and we develop new materials, that this balance may actually move to higher, or lower voltages than it currently is, but then do you redevelop everything for a marginal gain.

Where it isn't a marginal gain, then equipment is chosen at different voltages - but such a choice comes at a cost.

I have worked on many sites where all industrial equipment is at 660v, 1000v, 1.5kV or 3.3kV etc in order to reduce the current over large distances, however the cost is limited choice of switchgear, cables etc.

Ultimately its best to have a single standard, which whilst isn't the most efficient in all cases is sufficiently efficient that the advantage of simplicity outweighs the complexity of multiple standards
 
C

Cookie

-
  • Thread Starter Thread Starter
  • #28
Not really, the whole wiring systems are designed around 230/400v rather than 400v

Switches and breakers are the most obvious, but my whole point is there are and have been other voltages, but the balance of advantages/disadvantages appears to work out around the 230/400v mark which is why it has ended up being the voltage range of choice.

It may be that as technology advances, and we develop new materials, that this balance may actually move to higher, or lower voltages than it currently is, but then do you redevelop everything for a marginal gain.

Where it isn't a marginal gain, then equipment is chosen at different voltages - but such a choice comes at a cost.

I have worked on many sites where all industrial equipment is at 660v, 1000v, 1.5kV or 3.3kV etc in order to reduce the current over large distances, however the cost is limited choice of switchgear, cables etc.

Ultimately its best to have a single standard, which whilst isn't the most efficient in all cases is sufficiently efficient that the advantage of simplicity outweighs the complexity of multiple standards
You're forgetting the history. The world started off with 110-127 volts. Eventually 127/220 in that 110-127 volts was just to low as it could not meet the needs to heaters and motors. Then came the discovery that the advantages associated with 220 volt could be extended to small equipment and associated branch circuits. 220 became the norm- hence why the schuko plug is not polarised.

When 220 volts became the norm for all single phase equipment, people realized that 220/380 met the needs of ever larger motors in typical buildings and long public supplies.

The thing is, today we are stuck on a dual voltage system without any investigation made if 400 volt single phase equipment might be more practical than 230 volt equipment.
 
J

Julie.

Esteemed
Arms
You're forgetting the history. The world started off with 110-127 volts. Eventually 127/220 in that 110-127 volts was just to low as it could not meet the needs to heaters and motors. Then came the discovery that the advantages associated with 220 volt could be extended to small equipment and associated branch circuits. 220 became the norm- hence why the schuko plug is not polarised.

When 220 volts became the norm for all single phase equipment, people realized that 220/380 met the needs of ever larger motors in typical buildings and long public supplies.

The thing is, today we are stuck on a dual voltage system without any investigation made if 400 volt single phase equipment might be more practical than 230 volt equipment.
No, not forgetting, but the first generation and distribution of electricity was in the uk in the 1880s it distributed ac 250v and 40v for different types of lighting.

I think it was in Godalming

Next was 110v dc in London


I certainly don't think we arrived at ~230v by accident without any thought, in Germany for example they specifically altered all their equipment from 127v to 240v to take advantage of the lower current, without too many issues with high voltage - other countries followed similar changes settling at various voltages mainly in the 200-250v for household and higher for industrial.

The compromise of 230v is fairly recent in those terms
 
C

Cookie

-
  • Thread Starter Thread Starter
  • #30
No, not forgetting, but the first generation and distribution of electricity was in the uk in the 1880s it distributed ac 250v and 40v for different types of lighting.

I think it was in Godalming

Next was 110v dc in London


I certainly don't think we arrived at ~230v by accident without any thought, in Germany for example they specifically altered all their equipment from 127v to 240v to take advantage of the lower current, without too many issues with high voltage - other countries followed similar changes settling at various voltages mainly in the 200-250v for household and higher for industrial.

The compromise of 230v is fairly recent in those terms

What investigation is there of 400 volts? Remember that incandescent bulbs no longer play a role where high voltages mean higher gas fills and thinner, longer, cooler running filaments. LEDs can be fed via driver. Caps and resistors can drop 400 volts to the required series parellel voltages.
 
Lucien Nunes

Lucien Nunes

-
Mentor
Esteemed
Arms
The gist of the OP's question is why not make the default single-phase voltage, i.e the lowest voltage available on the system, 400V rather than 230, regardless of the phase arrangement. So discount whether it's Y or delta, single or three phase, and just consider whether 400V light bulbs, hairdryers, phone chargers etc. are sensible and practical and worth the saving in copper.

The answer I suspect is no.

Historically, the choice of voltage was significantly dictated by both carbon-arc and filament lamp design and 120 years ago, both worked better at 120V than 240. Metal filament lamps are stronger, last longer and are more efficient at lower voltages (hence 12V halogens etc.) In the UK, we actually preferred 120V lamps in series pairs for certain stage lighting purposes instead of 240V and projector lamps were 120V fed from a transformer, because 230V lamps were so fragile and inefficient. We got good at making 230V general purpose lamps but 400V was basically unachievable, so there never was a 400V incandescent lighting option. None of that really applies in 2020.

The fragility argument also goes for many wound components, a small 400V transformer primary or relay coil is more expensive to make and more prone to failure than a 230V one, due to having many turns of very fine wire. Even 230V can be a problem - many small mechanical timeswitch motors (e.g. the defrost timer in the freezer and plug-in timers) actually used a 120V or lower voltage motor, fed by a capacitor dropper, because a 230V type would be too expensive and fragile. 400V would be much more of a problem still.

Discharge lamps with ballasts dictate their own voltage and the ballast takes up the difference between that and the supply. So a metal halide lamp running on 400V will take the same current as one on 230V, just at a lower power factor as the (more expensive) ballast has to drop an extra 170V. Only a transformer would solve this.

But, the main event is the switched-mode power supply, where the electronics on the primary side have to operate at the peak voltage of the supply. In most electronic devices, and any appliances containing electronics, the incoming 230V AC is rectified and smoothed to 320V DC, whereas on 400V the DC rail would be 560V. This requires both smoothing capacitors and chopper transistors of a different tier of performance, which certainly with the components available today would significantly impact the price. 560V is definitely at the top end of what electrolytic capacitors are capable of, and at this voltage it is not uncommon to have to use series pairs with balancing resistors. Possible, but probably not economic, given that many such power supplies use so little power that they would not contribute to any realistic saving in copper. Really small loads that use capacitor droppers, like the ballasted discharge lamps, would simply have to use a more expensive capacitor and drop more volts, with no saving in current.

Therefore I think with the state of the art, small power and lighting is still best served in the 120-230V range, with advantages to both voltages but increasingly in favour of 230V now that filament lamps are not a driving factor.
 
Last edited:
S

Simon47

-
Esteemed
Arms
Given that the idea of switching to 400V delivered as 2 legs of a 3P system, I'm surprised there's been no discussion about how the change coukd be made. It makes me think of the old joke about the tourist asking a local how to get somewhere - only to be told "I wouldn't srart from here".
With the change, single phase systems would now have two line conductors - so you now need 2 pole protection and switching for everything. So you're no needing a partial rewire of every property. Lights looped at the rose now need altering to take the second line down to the switch & back - physically you may be looping at the rose, but electrically the same as looping at the switch and needing a partial rewire. And of course, you'll need to replace most of your accessories to make everything 2 pole switched. And all your plugs will need replacing for ones with 2 fuses - I remember they had some of those at school for the 110V stuff run from 55-0-55V supplies.
So we've replaced all the CUs, partially rewired, replaced most of our accessories and pkugs and ... we still haven't addressed appliances.
So we also persuade everyone to replace their fully servicable appliances for new ones designed for the higher voltage. And they will be new ones as no supply of second hand ones. The day someone suggests that to me, they will learn some "interesting" vocabulary - unless they are offering to pay for it all.

Of course, there is the alternative of adding a stwp down isolating transformer between the meter and CU - at a cost, and if there's room in the modern shoeboxes.

And what do we gain ? Absolutely nothing at all until EVERY custoner on part of the network has been converted.

Conversely, any custoner is free to ignore the DNO provided earth and make their own arrangements - limited only by their access to sonewhere for a suitably earth electrode (system).

Lastly, who here has has the experience of connecting a 110V item to 240V ? Occasionally it's forgetting to check the position of the voltage selector switch. Once in my case it's been someone sending me the wrong (single voltage) part. But generally the results "aren't pretty".
So I would forsee a lot of blown up kit as people plug their 240V items into 400V supplies. Now they wouldn't ? I can assure you that a lot if oeople would - they have no idea what voltage is.
I recall at a previous place, the ladies in the retail shop asked the maintenance guy for some wire cutters. Why ? To cut off the plug and fit a new one on the christmas tree lights - it never occurred to then that the reason for an "odd" plug could be that the lights weren't 240V.

So, woukd 400V be a good idea ?
Possibly - but only if you don't start from here!
 
C

Cookie

-
  • Thread Starter Thread Starter
  • #34
You would not need 2 pole switching except at the consumer unit.
 
Lucien Nunes

Lucien Nunes

-
Mentor
Esteemed
Arms
It doesn't have to be two legs of a 400/230V system. One night, the DNO could uplift your local 400/230V transformer and drop a 690/400 in its place, and presto! 400V Uo in your house.

Switchovers from one voltage or frequency to another and DC to AC have all been done before. When the National Grid drove a rollout of standardised voltage and frequency, electricity suppliers would take your appliances and either modify them for the new supply or replace it if not possible, just as gas appliances were converted from town gas to natural gas. In the museum we have appliances originally made for non-standard voltages that have been reworked and the new voltage engraved onto the plate. E.g. a Hoover vacuum cleaner made for 210V that had a replacement armature fitted and '240V' stamped over the 210. Until recently, a church with a 1920s organ blower wound for 200V was running it from 400 via a transformer supplied and fitted in the 1940s at the electricity supplier's cost. Sites with large inventories of DC plant used to install rectifiers to keep it all running when the mains were converted to AC.

The greater number of appliances in use today and the impracticality of converting most of them makes a repeat of that exercise near impossible, though.
 
Instyle LED Lighting Specialists UK
This official sponsor may provide discounts for members

Reply to Practicality of 400 volt equipment in the Electrical Forum area at ElectriciansForums.net

SuperlecDirect - ElectriciansForums.net Electrical Suppliers
This official sponsor may provide discounts for members
Top Bottom