Triton Shower Install, Plumber or Electrician?

MR_R_SOLE

Old-Salt
Right in the interest of CDRILS or what
ever they are called this week. I have consulted the NICEIC the oracle for this type of debate ( one of the main bodys that checks compliance to regulations for Electrical Contractors in the UK). One of there senior Enginers ( whom is also a mate of mine).
Said, although according to BS7671 a like for like swap of an electric shower would technically not be notifiable to BC. Good practice would to be to issue a Minor Works certificate and check appropriate disconnection times of devices and ZS and notify BC. This would serve two purposes one being a record for the installers insurance and the other for the home owner to keep a copy of just incase it all went tits up and caused a fire.

So I shall admit I was wrong to insist that BC be notified. How ever in good practice this is what I would personally do and would recommend to anyone who is considering having such work carried out.
Also @Himmler74 if your going to jump in on a topic please ensure you are actually discussing the subject matter and not a
thermostatic shower

Kindest regards
A slightly humbled
MR_R_SOLE
 

lecky

War Hero
Please im not a Sir, I was a mere OR albeit with a trade and an education. I hate TEAMS with a passion. I take it you've seen this years L3 design exam. I genuinely feel sorry for the ones that have to pass that. It's nails for a bunch of young pepole that's had to deal with remote learing . I'll happily admit I had to open the Regs and the OSG in order to work it out myself.
Don't trust any published model answers...the Exam boards plant mistakes in there....just in case anyone is stupid enough to show the kids before the Exam...like some idiot in Birmingham did the other year, with an EAL Principles Exam. All the kids got "perfect" answers, including all the planted mistakes. Turned out he "accidently" might have left the model answers up on the Whiteboard and went to the toilet. His kids photographed the answers on their phones.
Who are you with? EAL or C&G?
 

MR_R_SOLE

Old-Salt
Don't trust any published model answers...the Exam boards plant mistakes in there....just in case anyone is stupid enough to show the kids before the Exam...like some idiot in Birmingham did the other year, with an EAL Principles Exam. All the kids got "perfect" answers, including all the planted mistakes. Turned out he "accidently" might have left the model answers up on the Whiteboard and went to the toilet. His kids photographed the answers on their phones.
Who are you with? EAL or C&G?

We're C&G we all have encrypted memory sticks with lesson plans and the answers to the designe questions and knowledge packs on ( double checked by a few senior members of staff). Plus we actually work out the install amd calcs ourselves too before we start teaching then it's a Chinese parliament of staff to sort the wheat from the chaff so to speak.

Don't get me wrong some " Coaching" happens but nothing that would cross the line to cheating.

A little like coaching on a Matts range day. We advise but there's no one taking there place at the point and firing for them.
 
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I have an electric shower unit to install, it's a fairly basic Triton and a near like-for-like swap. Cold water and power entry at the same points.
Sort of thing I might have done myself a while back but now I'd prefer to get a professional to do it.
My question is, would this best be done by a plumber or electrician? My guess is that either would be able to do it so it's a question of what the norm is and whether any sort of certification is required and if so, who would provide it?

Thanks in advance
You will have to get a man in .
 

lecky

War Hero
Oh FFS!..... How to design and write up a running commentary, that is informative, easy to read, and imparts all the information to the reader without causing eyestrain, mind block, and contains sentences, short paragraphs, punctuation, and all separated by .................... visible........................ gaps................;)


PS:-
Have you ever worked on the tools, hands on, on site, for any length of time, either domestic or industrial, just wondered :???:
Calm down. That was just me making a point that a little bit of knowledge is a dangerous thing...I'm not setting out to teach Design to anyone on here, so I don't care how you read it, or how it's read...I'm just illustrating that there's more too it than all lights in 1 mm sq, all rings in 2.5mm sq, all Cookers in 6mm sq and all Showers in 10mm sq....which some people on this thread have demonstrated that they think that's the limit to all they need to know.

Anyway, have you spotted any technical flaws in the advice I've illustrated?
No?
Thought not?

Have I been on the tools On Site?
Ha ha. Really?
Do you think they'd allow me to teach and the staff of Industrial and Commercial Clients, in Design, 2391, Domestic Installers and the Reg's, along with the Regional JIB and Councils entrusting me to teach and assess their Apprentices, over 4 Year Programmes, if I hadn't?
 

lecky

War Hero
We're C&G we all have encrypted memory sticks with lesson plans and the answers to the designe questions and knowledge packs on ( double checked by a few senior members of staff). Plus we actually work out the install amd calcs ourselves too before we start teaching then it's a Chinese parliament of staff to sort the wheat from the chaff so to speak.

Don't get me wrong some " Coaching" happens but nothing that would cross the line to cheating.

A little like coaching on a Matts range day. We advise but there's no one taking there place at the point and firing for them.
We use EAL.
We're left to write our own Lessons and power points. Our College won't spend the money on Teaching packages. They're even asking us to estimate how much stock we will need for the workshops for next year, before we know how many Apprentices we are going to get.

We get two sorts of Apprentices. Those who have a great attitude to learning, helped along a bit, if they've got a bit of Aptitude for the Subject...and those who think they're on some sort of attendance course and they'll get given the qual at the end. Some of the last lot have got a relative for an Employer.
Fortunately for us, the second group usually get sacked by their Employer, even at times when their Employer is their Dad. Thankfully, it happens long before they get to be a an underwater parachute for our Achievement figures. Last years Written Principles Exam first sitting saw one third of our students fail with an average score of 29% whilst the other two thirds passed with an average score of 71%, with as many Merits and Distinctions as Passes. Three lads got into the 90%+ Scores. The gaps between the "knows" and the "don't knows" was that wide. What can you do?
 

lecky

War Hero
What is the attitude in the trade to the customers who themselves source the items to be fitted?
Is it seen to be helpful or something that slides away at their profit margin?
I don't want to appear a cheap-skate as often it means getting an item of my own choice.
For example, I've also got a Samsung hob to fit, chosen mainly because the wife prefers the controls & appearance. I wouldn't expect to ask the lecky to hunt one of those down. On the other hand, when it come to replacing the fuse box (or whatever they are called these days) it seems a no-brainer to get the electrician to supply it.
If you've sourced the items yourself and they've got a British Standard, then nobody can argue...not that they would, unless they didn't want the business off you.
Sometimes the Electrician gets a discount at the wholesalers, which can sometimes mean they can get the Components cheaper than you...and other times, they''ll keep all their discount and add a bit for extra "skim." just depends how the business is going and what they think they can get away with.
Prices are easily checked on line for Components. so there's no harm in looking on Toolstation or Screwfix first. Then asking what the Electrician can get it for?
After that the job is usually priced on what's known as a "per Point" basis. A "point" is a separate location along the run of a Circuit, at which the Electrician has to carry out work. So for instance: If they've got to route the shower Circuit, then the first "Point" will be the work at the Consumer Unit, the next "Point" will be at the Double Pole Pull chord switch in the Bathroom, then the Third "point" will be the Shower Itself. Depending where you are in the UK, expect to pay anything from £75 per point, to £300 per point from the chancers in that there Lon-don.
 

MR_R_SOLE

Old-Salt
We use EAL.
We're left to write our own Lessons and power points. Our College won't spend the money on Teaching packages. They're even asking us to estimate how much stock we will need for the workshops for next year, before we know how many Apprentices we are going to get.

We get two sorts of Apprentices. Those who have a great attitude to learning, helped along a bit, if they've got a bit of Aptitude for the Subject...and those who think they're on some sort of attendance course and they'll get given the qual at the end. Some of the last lot have got a relative for an Employer.
Fortunately for us, the second group usually get sacked by their Employer, even at times when their Employer is their Dad. Thankfully, it happens long before they get to be a an underwater parachute for our Achievement figures. Last years Written Principles Exam first sitting saw one third of our students fail with an average score of 29% whilst the other two thirds passed with an average score of 71%, with as many Merits and Distinctions as Passes. Three lads got into the 90%+ Scores. The gaps between the "knows" and the "don't knows" was that wide. What can you do?


I guess we're lucky in that respect as to lesson plans. We're really luck that we have two BEng holders in the department that will go through the syllabus and correct mistakes before they are passed on to the rest of us.

As for materials I've already raised concerns about the national shortage of construction materials in the UK and asked can we get our budget early and order in some stock now as opposed to August amd hoping for September delivery's ( other construction departments have expressed the same concerns as roofing batting is over £100 a bundle atm!) Only to be told no you will have your budget in August and crack on.

I can't wait until our budget stretches to a few drums of twin and skin. 1 bundle of 20mm galv and a few MICC glands and potts. As well as trying to reorganise our stores as out Thech is useless. But what would I know I only ran a Electrical Contracting business, before that a supervisor for some of the biggest Electrical company's in the UK.

To be fair to your earlier post I missed some of your deliberat mistakes first time around but I had a few beers and was skim reading as I'd been lecturering principles all bloody day.

Don't get me wrong I love the job and it's very rewarding seeing the next generation actually doing stuff for them selves but some of our management haven't been on a site in 3 decades so are reluctant to change. I've came straight from industry less than a year ago and still keeps hand in with helping out other sparks with design and RAMS on occasion.

The future I'm afraid is not too bright. I had a class today that took me over an hour to get them to wright thier names on 6 pices of paper work so we can submit.

On the other hand we have high flyers that will be Contract managers within ten years or owning firms that will go on to do great things.

May I ask how you are going about teaching renewables? I'm struggling like feck to get the kids to get thier heads around the fact that you can produce power from other sources than fosssile files.
 

MR_R_SOLE

Old-Salt
If you've sourced the items yourself and they've got a British Standard, then nobody can argue...not that they would, unless they didn't want the business off you.
Sometimes the Electrician gets a discount at the wholesalers, which can sometimes mean they can get the Components cheaper than you...and other times, they''ll keep all their discount and add a bit for extra "skim." just depends how the business is going and what they think they can get away with.
Prices are easily checked on line for Components. so there's no harm in looking on Toolstation or Screwfix first. Then asking what the Electrician can get it for?
After that the job is usually priced on what's known as a "per Point" basis. A "point" is a separate location along the run of a Circuit, at which the Electrician has to carry out work. So for instance: If they've got to route the shower Circuit, then the first "Point" will be the work at the Consumer Unit, the next "Point" will be at the Double Pole Pull chord switch in the Bathroom, then the Third "point" will be the Shower Itself. Depending where you are in the UK, expect to pay anything from £75 per point, to £300 per point from the chancers in that there Lon-don.

Pricing buy point is now old hat, you can get a decent freelance estimator for a few hundred quid. Far more accurate than point to point pricing.
That's not to say point pricing on domestic is fine and will lead to good profits. But when going commercial or industrial then you need a good Estimator.

On another point the mark up on materials supplied bh the contractor usually takes care of remedial work and adds to profit. I didn't run a business for a wage I ran it to make a wage and then dividend.

Any client of mine that asked for a break down of a quote was told x amount labour x amount materials. If they argued over the cost of materials I used to just ask do you go to Tesco and ask wjat they paid for a cabbage and what there mark up was?.

Why should I explain to someone the inner workings of my business model. Would they show me there pay check and bank stamens for the past 3 months just so I could see if they could afford the work?
 

MR_R_SOLE

Old-Salt
I'd back up the call for a Triton, especially one that is fairly mid- range.

Very forgiving to install, can usually fit one wherever the water and cable is, comparitively, to each other.

If you keep the power fairly modest, you won't need to upgrade the cable, it all depends on your installer, how competant they are..... I was a plumber, but usually happy to fit like for like on the electrics, if they weren't fitted on bell- wire, I had a sparky as a back- up.

Could you please elaborate on this?,. For example what factors ( external fsv
I'd back up the call for a Triton, especially one that is fairly mid- range.

Very forgiving to install, can usually fit one wherever the water and cable is, comparitively, to each other.

If you keep the power fairly modest, you won't need to upgrade the cable, it all depends on your installer, how competant they are..... I was a plumber, but usually happy to fit like for like on the electrics, if they weren't fitted on bell- wire, I had a sparky as a back- up.

Could you please elaborate on this?. What are the de rating factors that need to be taken into account when selecting protective devices and cable?.
 
Could you please elaborate on this?,. For example what factors ( external fsv


Could you please elaborate on this?. What are the de rating factors that need to be taken into account when selecting protective devices and cable?.

I assume his elaboration would consist of exchanging a unit for one with the same kw output.

It's safe to say if a shower has been in for 5-10 years without killing the family or starting strange fires then the infrastructure is sound.
 
Oh FFS!
How to design an Electrical Circuit:
1) Find out the Wattage of the intended load/s that are Resistive and divide through by 230v if single phase. If its a three phase it's; Wattage/Line Voltage(400) x 1.732 (square route of 3) x Power Factor (if there is one) x Efficiency ( if there is one). If It's Gas Discharge Lighting it's; Wattage x 1.8 For In rush Current/ 230V. End of step one. You've found the Load Current Ib. ( The "I" is the symbol for Current and the "b" stands for "Burden" as in burden on the Circuit) You now know that Current is going to be dragged through your Circuit and can rate your Switches, Junction Boxes and Terminals to exceed Ib, or you'll eventually melt them, or weld them shut.
2) Now choose a Protective Device that equals or preferably just exceeds Ib. Cb types are; Type B for Resistive Loads, Type C for Resistive/Inductive mixed Loads and Type D for mostly Inductive loads. The rating of that Device ( i.e.32 Amps) is now your "In" or nominal current rating for your device
3) Next, calculate IT. IT = The Tabulated Current Carrying Capacity for the Cable, so called because you have to gather information on what could increase heat on a Cable, along your intended route for the Circuit. Heat is the enemy of cables, particularly PVC and Copper cables, as Copper has a Positive Temperature Coefficient, meaning it's Resistance goes up with heat ( and Current carrying ability subsequently goes down), whilst PVC has a Negative Temperature Coefficient, meaning its Resistance goes down in increasing heat....neither of those effects are what you want in a Cable Conductor or Insulator! There are Correction Factor Tables in the Regs, or the On Site Guide: the commonly used ones are Ca= Ambient Temp Correction Factor, Ci= Insulation Correction Factors (through insulated cavity walls, not the Insulation in Lofts and Ceilings, Cg= Grouping Factor for cables heating each other up, Cc is for cables buried underground in Soil, whilst Cf is for the old Semi enclosed rewireable Fuses, which can be too slow to clear Overloads effectively ( don't use them.) Once you've gathered the data ( there are more correction factors than this but these are the most common) then calculate IT. IT= In ( CB Rating)/ Ca x Ci x Cg x Cf x Cc. Now you've found IT make a note of it.
4) Establish the Installation Reference Method? Are you clipped Direct? Are you in Conduit or Trunking? This too has a heating effect to a lesser extent and effects the ability of the Cable to carry the Current. It comes out of a Table in the Reg's in the Form of a letter Code from the Alphabet.
5) Now chose a cable type and look it's Current Carrying Capacity Table up for its particular table in Appendix 4, tables 4D onwards of the Regs. Look for the Column on the table with the Letter code you found earlier for the Installation Reference method and look down the Column of figures until you reach a number that's the next size up from IT, that you calculated earlier. You've just found the IZ for your cable. IZ Is the Current carrying capacity of your cable. "Z" As a reminder that it's the last letter of the alphabet and the last thing you should be deciding is the cable size...not the first. Now look across from the IZ number on the table and read off the cable size in mm sq that you should be using.
6) Measure your length of run in Metres. Now calculate your Voltage Drop by reading the corresponding milli V/Amp ( of Ib)/ metre in the IZ tables. Multiply all those values and check your chosen cable comes under the Voltage Drop Limits in the Appendix 4, the Voltage Drop table. If the Voltage Drop exceeds the percentage limit listed, try the next size cable up and see how you get on for Voltage drop with that ?
7) Now look up the R1 and R2 prospective resistance rating of your Line and CPC in milli Ohms/metre and calculate that for your run. You'll find the tables in the on Site Guide, or in the back of Guidance Note 3 Appendix B. Add it to your Ze (0.35 for TNC-s, 0.8 for TNS and less than 200 for TT). Then adjust for temperature as the Resistances in the table were calculated at 20 degrees c. Inside ambient is 30 Degrees C using the multiplying factor tables in the On Site Guide. You've now got your Theoretical Circuit Zs in Ohms. Go to the Protective Device Zs tables in Part 4 of the Regulations and check the Zs you've just calculated, comes under the maximum Zs ( x 0.8 for indoor circuits) listed in the table for the In you chose in step 2. ( The Max Zs tables in the On Site Guide are already Temperature corrected for indoors, so don't multiply by 0.8 if you are using these tables.) If it doesn't then your fault current isn't going to be cleared in time by the Protective Device, before the Fault Current starts thermally shocking the Conductor. You might have to fit an RCD to the Cb, just to get it cleared in time. but beware, some Special Locations require an RCD and a Zs lower than the Max. In this case, fit a Distribution Circuit of a larger CSA cable from the Consumer Unit, to a Distribution Box of a Discriminatory Protective Device, to reduce Zs and shorten the length of run to the Final Circuit. This should reduce the Zs.

If any of that didn't make any sense, or you don't have the means to do the Cable Calcs, then you really have no business Installing Circuits...especially the ones in your own home?
Hope this informs?
Mr R Sole and I currently have identical employment. I teach JTL and On Site Apprentices the basics in level 3 Design amongst other things.
Or, alternatively.
Get a qualified electrician to do the job.

Water and electricity, not doing anything with those two combined.

Simple plumbing I'll happily do, simple electrics, wiring plugs and making an extension lead, no problem.

ANYTHING that involves more technical stuff then no. I'd rather pay for a professional person to do the job and do it properly and safely.
 

MR_R_SOLE

Old-Salt
Could you please elaborate on this?,. For example what factors ( external fsv


Could you please elaborate on this?. What are the de rating factors that need to be taken into account when selecting protective devices and cable?.


Yes I can, Grouping factors, amabiant temperature,.method of installation. Does the cable run through walls/ Lofts with thermal insulation?. These will call effect the current carrying capacity of the Cable. Also you need to ensure your protective devices will operate within outlined parameters.

Get a spark in to do the job.
 
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Yes I can, Grouping factors, amabiant temperature,.method of installation. Does the cable run through walls/ Lofts with thermal insulation?. These will call effect the current carrying capacity of the Cable. Also you need to ensure your protective devices will operate within outlined parameters.

Get a slark in to do the job.

You are my tutor who bored me to sleep after a 26 hour shift changing a shaft generator, I claim my £5. ;)
 

MR_R_SOLE

Old-Salt
I have that effect on a lot of students, I find a 1 meter steel rule slammed violently against a desk seems to wake them up a little and get the rest to put there bloody phones down ( albeit for about 30 seconds )
 

lecky

War Hero
I guess we're lucky in that respect as to lesson plans. We're really luck that we have two BEng holders in the department that will go through the syllabus and correct mistakes before they are passed on to the rest of us.

As for materials I've already raised concerns about the national shortage of construction materials in the UK and asked can we get our budget early and order in some stock now as opposed to August amd hoping for September delivery's ( other construction departments have expressed the same concerns as roofing batting is over £100 a bundle atm!) Only to be told no you will have your budget in August and crack on.

I can't wait until our budget stretches to a few drums of twin and skin. 1 bundle of 20mm galv and a few MICC glands and potts. As well as trying to reorganise our stores as out Thech is useless. But what would I know I only ran a Electrical Contracting business, before that a supervisor for some of the biggest Electrical company's in the UK.

To be fair to your earlier post I missed some of your deliberat mistakes first time around but I had a few beers and was skim reading as I'd been lecturering principles all bloody day.

Don't get me wrong I love the job and it's very rewarding seeing the next generation actually doing stuff for them selves but some of our management haven't been on a site in 3 decades so are reluctant to change. I've came straight from industry less than a year ago and still keeps hand in with helping out other sparks with design and RAMS on occasion.

The future I'm afraid is not too bright. I had a class today that took me over an hour to get them to wright thier names on 6 pices of paper work so we can submit.

On the other hand we have high flyers that will be Contract managers within ten years or owning firms that will go on to do great things.

May I ask how you are going about teaching renewables? I'm struggling like feck to get the kids to get thier heads around the fact that you can produce power from other sources than fosssile files.
The whole Renewables thing used to take up a unit all of its own with EAL, but that's died a death. The basics of PV Layouts, Wind Turbines, Hydro and Micro-Hydro is all that's on our Syllabus and all folded into the Principles, as an Aim and Objective in the Supply and Distribution Outcome. Amazingly, Ground Source Heat Pumps and Biomass is no longer a requirement, but CHP Boilers are? Oh well.

After we've done basic Generator theory and before we do the Supply and Distribution network, I'll cover renewables. I scaffold their understanding, by going through the basics of Turbines and compression blade stages... I'll use basic jet engine analogies...then substitute wind and water for the Air and Steam. Childs windmills get an airing...being run under a tap on one edge, or blown on at various angles?
Then for hydro, I'll challenge them with some simple problems:
Your water's running out....what can you do? Your river water's full of leaves and debris...how do you stop it getting in your turbine? How do you control your water flow rate? Get them discussing solutions. Then up comes the Power point and we relate our solutions to Forebays, Penstocks and Recovery pumps on the System Diagrams and Pictures. We might go on to classify the micro Hydro from Pico Hydro by their wattages, then they'll finish off writing a gapped handout, for notes and to check understanding.
Similar approach for Wind... only we will look at Propeller engines and chat about blade pitch, then ask them questions related to what "Yaw" might be and how it matters with Wind Turbines...then ask them how we are going to achieve Yaw Control for the Wind Turbine? Frequency variation gets discussed...DC Generation and storage becomes the solution
When that's over, up pops the Power Point with an exploded view inside the Wind Turbine Nacelle and we chat about Yaw motors and how they might control direction in concert with comparative wind pressure sensing on the sides of the nacelle on the one hand, or tail rudders on the other. Then a Gapped Power Point for completion.
For the PV, I will explain Cell operation and get them to relate it to Capacitors, as I would have just finished teaching Electronics. Then I will ask them if they think the Cells DC or AC? If each Cell produces a tiny Voltage, how would you have to connect them? Series or Parallel? (You're embedding previous learning from Dc Batteries)
Once we've done that, we will problem solve again: What happens if there's dust, leaves or even Bird shit on the Cells? What would be the implication for the string of series connected cells if one was open circuited? What simple, cheap little Electronic Device could you strap across each cell, in case one of them went open Circuit and stopped the string of cells from producing a Voltage? Usually, someone will come up with "a diode" sooner rather than later, so that's embedding previous learning as well.
Then we will have a chat about PV system arrangement and how it's on all the time whilst there's sunshine...so what are the safety implications when you enter a Building with PV? That usually leads to talk of Safe Isolation...and we get on to the DC Isolator and the AC Isolator...what colours differentiate the two and the need for a Dual Power warning label usually gets dragged out of them? Then we chat about Invertors.... again something fresh in their memory from Electronics. Then we discuss the Voltage output that may, or may not come off the PV array...what do they think the regulator will allow and what level might be cut off? All the while, the system should be taking shape in their imagination?
Finally, I'll give them a jumbled set of cut out paper Blocks, representing the two Isolators, the array, the Invertor, the CU and the Feedback meter and ask them in small groups, to arrange the Blocks in a logical order, to represent the PV system arrangement. Sit back, watch and listen for arguments, see who's leading the group and whose taking a ride...then put the guys taking a back seat on the spot, by asking them to put the mistakes in the arrangement right. (They soon learn that if they look involved, they won't get put in the spotlight) Finally, when the arrangement has been checked, out comes the handout and they fill the necessary in: Sketch the correct Block arrangement? Label what each block represents? What's the Function and identifying features of each Block? What are the dangers and under what circumstances might you operate the AC Isolator, or the DC Isolator, independent of each other?
As for CHP Boilers, they're so pathetic at creating Electrical Power that it's easier to quickly describe it, then let the students pick it apart...it's just too obvious that it's a rip off.

I always start a lesson on the premise that they haven't got the first idea. So I will "scaffold them" to where they need to be. I'll use the historical development and discuss the problems that early inventors faced. I'll use analogies, metaphors and similes to support their understanding... much of it is discussion...cause and effect...logical progression...Problem and Solution? The sort of thing you couldn't or wouldn't put in a text book. I'll even get them to reverse Engineer a situation.
I'm doing most of the talking, but you better concentrate, or I'll put you on the spot. No **** is allowed to get away with "I don't know." That just attracts simpler and simpler questioning until you crack...then we build you back up to where you first left off!
I put in Formative assessments at the end of each Outcome. Employers and Training Providers get their latest performance scores. The students know that. Everybody involved gets to know what each student is capable of long before the Exams. Levers then get applied for attitude adjustment... or the Employer usually sacks them before the end of the course.
Hope that helps?
 

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