star delta motor .....extra stop/start....415v abb

[chilliwilly]

QUOTE=netblindpaul;747950]Statute law precludes 400V a.c. control at this point in time.
If you don't know this, leave it to those who do.[/QUOTE]

Statute law eh, I thought all laws were statutory?

With me being a roofer I wouldn't know much about that but I occasionally do a bit of wiring for my aunt and my mum, infact only last week I put my mum a light buld in her stairs landing. And for my aunt I put a plug on her battery charger for her vibrator. So I think that makes me an electrician qualified enough to come on this forum don't you? Thinking this I managed to carry out the following jobs...

Yesterday I replaced a push station on a pillar hoist (Pelloby) that had 415v across the start button on the wand to control the 415 v coils. And replaced an Ellison resistance starter thingy on a calendar that had 600v fed to it from a slip ring motor thing.

This morning I wired up 6 x TP&N 400v isolators/dissconnectors that switch the supply to washing machines for a laundry install I'm carrying out.

In my work shop I'm building a control panel for a conveyor system that has "D" connector thingammi bobs that in turn have 12v-400v on various cores within the same cable. That in turn will supply further push stations for remote control, and condition stop indicator panel stations, the 12 v is for interfacing an old omron plc (what ever one of those is) that controls an auger feeder and sol valves.

And my work shop has crompton dol starters for my roller shutter doors which have 400/415v motors, and I used them to open and close this morning.

And I frequently work on them refigeration thingy systems that have star/delta units for for them compressor things with no neutrals or trannys supplying 110v to the coils and start buttons, some do have auto transformers with variable tappings though. Mind you though they have 400/415v fed to them with a small pilot motor fed directly from a button with 415v across the contacts.

Oh deary me, it looks like I have been breaking the law, and the niccy are coming out to see it on Friday for one of my initial inspections. I hope they don't mind me being a roofer who changed to be an electrician?

Oh no, what am I going to do?

I know, I'll shut shop all together for good and leave it to those who know there stuff. But that means my colleagues who are lift engineers will have to shut down all the goods lifts they work on, and my mate who has a garage won't be able to use his hydraulic lift to work underneath his customers cars.

Sir, can you tell me what will happen to me now? I can't face doing any hard time in jail, and all my money is tide up in assetts that also have third party investers, so paying a fine will be very difficult. I hope the judge knows his stuff and takes this into account that I'm a roofer and don't know any better like I would if I was a proper electrician like you.

Maybe I'll just go on one of those 1 week courses and become an electrician and live happily ever after.

 

[leespeed]

good rant chilly...lol right lets get something straight here....the star delta motor is only controlling a 5.5kw motor in the
cellar which is only a blower ...........the original install had a remote stop start at the organ on the wall, to remote start and
stop the motor ,that is why i was asking for any info to install a remote circuit prefferably 24v just for the remote start and stop .............hope this clears things up

 

[Darkwood]

Lets clear this up.... if the control circuit is within the same housing as the control gear then its often found that 400v is used as the control e.g. DOL starters with the buttons mounted on the lid, when operations are remote from the control gear then careful consideration has to be taken into account with regards the environmental influences, rating of control gear and where such systems are installed in a industrial environment then a reduced voltage control system should be installed. Im forever changing smashed, failed, abused control stations and buttons and when they do get damaged they usually try to carry on using them until they stop functioning. IP ratings often fail over time too so if the control point is suseptable to ingress whether it be liquid or solid then overall a SELV control system should be implemented. , i still come across 400v remote control on old systems that i would never consider safe to implement nowadays.

If exporting 400v control its often the case that the extra measures taken to ensure its durabilty outway the smaller costs of reducing the voltage in the first place, i rarely see an occasion where i would export 400v controls by choice but thats not to say your not allowed but in our industry of H&S, risk assessment and regulations it is good practice to export controls at safer reduced voltages.

There might not be a direct clause ruling it out but putting other regulations into practice and meeting both the health and safety and risk assessment requirements leaves little room for justifying its use in new control systems or even alterations to existing.

 

[chilliwilly]

Yes I knew what you wanted, I just couldn't see what the big issue was with the OPs comments.

Hope you get it sorted without thinking about it too much, use whatever you feel safe with.

 

[chilliwilly]

I know what you mean my learned friend, but two or more risk assessments are never identicle, and I can see why you think it more desirable to use elv rather than lv for controls. But until the EAWR, IET, and BS make it absolute and the niccy and the likes start snagging the use of 400v controls on local and remotes old and new. I will stick to my guns regarding circuit design and cable selection suitable for the respective environment, as always.

The laundry that I'm currently installing, will only have 5 core flexes fed from isolators mounted on steel trunking in turn fed by singles from a dist board, then run through the trunking, then from stuffing glands out to the machines, with no anaconda. And the (ECV) sol valve will be simply a latching e stop switching a 230/240v to the coil.

I would just like offer the following case scenario regarding control voltages.

If you have say a tp&n mcb or switch fuse from a switch cubicle supplying a feeder to a motor, via a control then a local isolator to isolate the motor to allow for switching off for safety to enable maintenance. You will always have 400v + within any enclosure that can be operated by persons, either from buttons, switches, or levers. So you will never get away from the fact there will be always 400v + present within circuits supplying, heating, electromotive, or lighting. Desite having the control on ELV, there wil always be the need to switch 400v + at some point within that circuit. Even on tri rated commercial deep fat electric fryer or a chargrill, the thermostats are 400v +, with no elv contactor switched by buttons.

The trouble that I find is when you introduce a ELV control to an LV thats been tried and tested for years, the transformers can burn out adding to additional downtime already associated with coils and the like burning out. Or a surge resulting in a brown out will cause the secondary voltage to drop sufficiently to release the 24v coil. Probably causing you to look for wiring faults that don't exist.

 

[Darkwood]

Chilly you trying to snag the use of 24v with senerio's that don't really happen nowadays.... i often use 24v dc power supplies that are S/C protected and overcurrent protected and simply shut down until fault cleared they actually aid in the detection and have options for signalling a fault is present, i wasn't having a dig at you personally or your set-up im just saying as it is.. im more industrial controls and have to catagorise the safety level of my control systems and 9/10 times this will be with the use of a safety relay, and also most measuring devices senses etc also are compatable with 24v dc as routine although other voltages exist.

On a tangent where you based as cleckhuddersfax is a very local name here and i suspect you dont live far from me?

 

[chilliwilly]

I live near Leeds, and I know you wasn't having a dig. Just adding your tuppence'a'penny as we all do.

I wasn't trying to snag the use of elv and rlv, I was just pointing out that until its made absolute that 400v control is unsafe. I will stick to my guns as I know that there is no way you will escape the fact that 400v+ will have to be manually switched at some point, either locally or remotely. That being the case I will still continue to use it on new and old systems for controls for basic stopping and starting.

In the case of most industrial systems that I work on, they do not incorporate the use of PLCs and other SS & EM devices such as counters and timers. They are more the traditional well engineered MTE, Crabtree, Ellison, and the like for cranes, conveyors, extraction, and HVAC. So as you can imagine with that being the case I will always maintain the existing standard of 400v+ controls that would be too expensive and uncompetetive to modernise. Somebody else could simply walk in after me and undercut my price of modernisation by sticking with 400v+ controls.

Whenever I do work on more complex control with PLCs and the like, then obviously I have to go with what ever control voltage they have implemented.

Anyway my learned friend all the best and keep up the good work.

 

[Knobhead]

I just hope you never get near a medium sized control system. With you’re attitude it will be a disaster.
I do hope you realise you included crane control in you’re list.
Safety, what’s that got to do with anything? It works, doesn’t it?

 

[chilliwilly]

Perhaps you would like to explain your point and your reason for your egrigrious comment?

 

[chilliwilly]

And what on earth makes you think that I have only worked on a control system for only a 1/2 horse motor?

 

[netblindpaul]

It seems that there is a lack of understanding of the difference between statute & civil law.

Also, why is it if someone suggests not complying with the latest version of BS7671 when they are doing an install or modification then it sees that they are wrong and must comply with this standard.
However, when it comes to electrical areas that are covered by other standards & statute law, people seem blasé in their interpretation and have no care for compliance with the statutory requirements?
I'll bet that most people who are working on electrical systems outside the scope of BS7671 do not hold copies of the standards & statutes to which they must be working?
In case you are not aware, in the event of a case, if you are not in possession of the relevant standard and statute to which you must be working then you will be deemed as non-compliant by the court.
Oh and the expert witness will make mashed potato out of you.

If you modify a machine control then you must upgrade it to current standards or, be prepared to face the music if it goes wrong, and, it may be a totally un-related incident.
If you are designing & implementing control system modifications then for your sake I hope you can prove competence & have suitable insurances in place, because due to FFI, you could easily be hit with a very large bill.

I can't understand the vehemence with which BS7671 is defended on this forum, and the total disregard for other more onerous requirements for electrical works, it is beyond my comprehension.

 

[chilliwilly]

Tell me then, to which document are you refering to that states that a 400v + controls are prohibited for use within the UK and Europe? It doesn't state in BS 7671 the NEC or the CEC or any document I am familiar with.

If you would care to read my previous comments you will see that I do use what ever voltage is present for extending, modifying, and designing, including 400v+, as the equipment is still readily available and manufactured by reputable companies such as crabtree, abb etc.

If what your saying holds any water, then my colleagues and myself will have to tell all our clients to switch of their distboards, cranes, lifts, catering, refrigeration, HVAC, and any 5 pin comando sockets supplying any fixed or portable equipment. Until they agree to have it upgraded to RLV or lower. And most of the sparks on here won't be able to fit or replace any tp mcbs, the country will come to a stand still.

 

[netblindpaul]

chillywilly,
You seem to have a total misunderstanding of what is considered a control system.
The NEC does not apply in the UK.
BS7671 does not apply to machinery & control systems.
Most of the descriptions you give above are power systems under BS7671, not control systems.
Do you even know what the standard for control systems is?
There are still limited allowed applications for 400V a.c. control, though they are few & far between.
You should if you are doing this work be stating in what cases this is allowed.
I know & pull clients on it regularly.
From your attitude this is going to end up in a slanging match which I am not prepared to enter.
If you are doing this work then you must have access to the relevant standards & statute law documents, so the requirements should be there in your reference library for you to refer to, I know they are in mine.
I can take this as far as you wish, but, I'm not willing for it to turn nasty, and the tone of your posts is going that way so I'm going to end my input to this thread here, as I am unwilling for this debate to turn into an abusive rhetoric on your part, which from where I am sitting it seems to be going.
I bid you good night and hope that your clients don't get into any bother as you could find yourself in big trouble.

I'll give you one final example, a client of mine had an accident with an FLT in their yard.
Their insurance company sent in investigators.
These investigators, found discrepancies with machinery elsewhere in the premises.
This resulted in the company being in breach of the terms of their insurance.
Thus the insurance company cancelled their policy forthwith and refused the claim as they were not in compliance with the terms of the policy and this could be proven, and was.
So, the company was then prosecuted for trading without insurance and there were several other issues.
There is more to this than meets the eye, the insurance non-compliances were nothing to do with the FLT incident.

Good Night & good bye.

 

[Darkwood]

Chilly you are confusing what is meant y control systems ...we are not talking about 3ph dist boards or commando style 400v plug and sockets when we work with these they are covered by the BS 7671 and are thus compliant ..... what we are discussing is machinery control systems that isn't covered by BS 7671, Lift systems have their own specific standards to to comply with too also out of the scope of the BS 7671, it may be the case that limit switches within the lift shaft may use 400v although not on the ones ive seen fitted, but the push buttons within the lift and call buttons will be ELV as they are prone to damage if not vandalism.

All the cranes new and old i work on have at max 110v at their pendants and due to this been at risk from getting damaged, caught up etc the modern cranes do use ELV.... i seen a few pendant cable lines ripped apart in my time and i would consider 400v swinging about at head height a dangerous senerio.


We are not talking about the LV side of any of your examples be it motor connections or heating elements but the control systems that operate this, considering even with 400v its still 230v to earth we do commonly have domestic switches etc that give the same potential to earth but the risk assessment in domestic has deemed this safe and where applicable measures are used like pull cords in bathrooms etc and zoning as well as rcd protection.

Lets try keep the theme of the debate to exporting control systems remotely to the control gear as was originally asked and not throw MCB's and plugs etc into the mix which are clearly nothing related to this debate.

 

[BrianDB9]

Statute law precludes 400V a.c. control at this point in time.
If you don't know this, leave it to those who do.

What law is that ? all this talk about 400 V being dangerous is crap , its standard practise in lots of places and it isn't voltage that kills you is it ?
Yes you can reduce the control voltage down to whatever you like but what are people saying all 400V motors need to be banned or something !

 

[chilliwilly]

My learned friend, I'm not confusing the voltage requirements of control with general enclosures, outlets, starters and other units. An enclosure is an enclosure and when bust open to expose 400v, is just as dangerous as 110v and would carry the same weight in court if there were evidence of neglect or incompetence. The pendant/wand that I changed on the pillar hoist the other day was a 415 volt control.

To push a button on to a 400v+ open or closed contact is no different to operating an mcb, isolator, or ellison type starter. In an old mill out Keighley way, the lift must be at least 60 years old, and I know for a fact the call button on the landing and inside the car, is 300v DC. I know the guy who services the lift and in his opinion there is nothing wrong with just because it has a higher control voltage than what is found on a modern high speed lift. And like me he has no intention of modifying it, he just carries on to repair and replace the contacts when they get worn.

There is also a hoist that is used about once a week for loading that in turn has 400v+ controls, as do the machine tools, compactor, and all the stops and gate/safety switches on a guilotine. And that is how they will stay until I am instructed otherwise.

 

[Darkwood]

What law is that ? all this talk about 400 V being dangerous is crap , its standard practise in lots of places and it isn't voltage that kills you is it ?
Yes you can reduce the control voltage down to whatever you like but what are people saying all 400V motors need to be banned or something !

Brian you are falling into the same trap as chilly in that you are confusing what is meant by a control system, we are not talking about the motor or the heating elements etc we are talking about the operating system which will have hands on interaction in most cases from a operator, its due to the very nature of this interaction with any machinery or control system that a risk assessment is needed to establish the risks and i would never consider it good practice in most cases to export control wiring for remote limits, sensors or push buttons at 400v.


Safety of Machinery-
EN 292 (ISO 12100 pts 1 & 2) Basic concepts, general principles for design
safety related parts of machinery and the general design principles.
(this references many other standards and outlines all basic principles)

EN 60204-1 (IEC 60204-1)
Electrical equipment of machinery -pt 1 general requirements.

(this is a very important requirement that outlines recommandations for safety related aspects of wiring and electrical equipment on machines)


Just a few EU Harmonized European Standards you really should know before you even attempt to fit and extra E-STOP or alter the control system of any machine.

 

[Darkwood]

My learned friend, I'm not confusing the voltage requirements of control with general enclosures, outlets, starters and other units. An enclosure is an enclosure and when bust open to expose 400v, is just as dangerous as 110v and would carry the same weight in court if there were evidence of neglect or incompetence. The pendant/wand that I changed on the pillar hoist the other day was a 415 volt control.

To push a button on to a 400v+ open or closed contact is no different to operating an mcb, isolator, or ellison type starter. In an old mill out Keighley way, the lift must be at least 60 years old, and I know for a fact the call button on the landing and inside the car, is 300v DC. I know the guy who services the lift and in his opinion there is nothing wrong with just because it has a higher control voltage than what is found on a modern high speed lift. And like me he has no intention of modifying it, he just carries on to repair and replace the contacts when they get worn.

There is also a hoist that is used about once a week for loading that in turn has 400v+ controls, as do the machine tools, compactor, and all the stops and gate/safety switches on a guilotine. And that is how they will stay until I am instructed otherwise.

The lift as already mentioned before has its own special regulations and standard to comply to of which i cant comment and as lift engineers they will hopefully be fully aware of and work or repair the lift within these standards.

The issue im sensing here is you seem to be on the mind set that if you work on an existing machine, crane hoist etc that may be design under past regulation and directives that you can leave it as such and just do the necessary but its the case that you need to do a risk assessment and decide whether a hazard exists do to its out-dated design ....simply replacing a pendant on a crane using the existing control set-up of 400v to pendant is in my mind short sighted.....we are talking about a cable and pendant that routinely gets hands on use and most likely takes alot of knocks.....so the cable splits by the pendant entry and the next guy using it is killed by the 400v ...how will you stand in court as you fitted the pendant because you'll be the first to have to explain why this wasn't seen in a risk assessment and im afraid saying if you quoted for the necessary alterations they wouldn't pay and you'd loose to someone else who would undercut you wont help you in court.

Yes im fully aware 400v exported controls are present within alot of dated machinery but when im told to make alterations or additions i include for any necessary updating to meet present standards, a one on one with the client expressing both my responsibilty and his own to his employees usually is enough and if not i wont put myself in that position.


Check this thread i started not long ago... 3 other electricians tried to repair it but failed when i came to it i knew i could get it going but it fell far short of requirements and ended it stripping the machine and starting again pic posted further on in thread.http://www.electriciansforums.net/c...uite-often-promised-tony-i-took-few-pics.html <--click link

If i repaired that board and even fitted the door back on the minute this deathtrap injured someone the responsibilty would be on my shoulders.

 

[chilliwilly]

I don't want you to think that I'm being cocky or unpleasant, but I fully understand and partially agree in what your saying, but can you give your proffesional opinion with the following case senarios...

1. A multicore with 415v to a pendant/wand, and a 5 core lead with 415v supplying a fixed item or portable equipment being used in the same environment.

2. Operating a switch, lever or a button that operate contacts that make or break 415v coils and other ancilliaries or loads.

3. Operating my roller shutter door from a 415v starter with no neutral to convert to 240v or lower, operating a lift call or car button with 300v DC or 415v across the contacts behind the button, and operating a TP thermostat on a catering appliance that switches elements and motors direct on line with contactor,and in turn has high limit stats in enclosures having surface contact temperatures of at least 180 deg c.

4. A 4 HP+ compressor operating a TP high limit switch to either stop the motor or operate a clutch when satisfied.

5. Replacing a gate or limit switch on an existing machine or plant, changing a mains board following a EICR and leaving code 3 departures only as reccomendations and noting them on the EIC?

6. A building site having temporary supplies from trannies and RLV cables being run over by mobile plant and the like.

In the case of the pendant/wand they should be assessed for risk from mechanical damage causing insulation failure and exposing live parts, I fully agree. Then if the assessment is found to indicate potential for danger, a reccomendation needs to made for another selection of containment for the cable, with a regular visual inspection. As would be the case for any other cable containing ELV RLV or LV. Or in your case a elv as a get out of jail free card, (but with no guarantee of defence if resulting in permanent damage or death to users).

But this can lead to total replacement of the whole system, in the event of long cable runs trannies supplying elv might not be suitable. Or a motor starter with remotes with only 3 ph and earth being fed to and from it. And any customer of mine will want to see evidence of regulation and or documentation to back up my decision to carry out such extremes in the event of replacing a coil, button and contact, thermostat, ellison external starter, etc.

 

[chilliwilly]

Yes that panel is a total mess, I used to come across stuff like that in foundries, and rubber compound plants, and at Thomas Faucettes in Castleford. Now that place was a death trap, how anyone wasn't killed in that place can only be known by a devine entity. I think they were still open the last time I drove past.

I can see where your coming from, but even if that was RLV, it would still constitute a code 1 departure. Clearly condemning the person arising in the event of a loss in resulting adding or replacing any parts to it without first removing the danger. My risk assessment of that would be to assess the risk of it being damaged again and place a crash barrier around it, or have it moved in a safer location. It could have been another enclosure such as a mains board with 400v + inside it.

But then again who ever decided to place it there either did or didn't exercise reasonable care within their design. I'll never know or find out.

The panel that I'm building at the moment is for a conveyor system for a small polymer factory, that is enclosed by barriers and guards incorporating gate switches. The exisiting system is a 415 v control, so I am simply replacing it because their is no more risk to users than what there already is. The only difference with voltage within the "D" connectors is the ELV to interface an omron plc that controls the process, and will switch the panel. And 4 of the motors are 100v connected in series. Yes that's right, 100v motors connected in series and wound to a point that they are 100% balanced regards to voltage and current, so they all run at synchronous speeds and don't stretch or compact the extruded polymer when its conveying on the 4 belts. An idea that some one came up with before my time, because they couldn't afford invertors to control the speed of the motors.