hi lads i have few questions: what is max disconnection time for site hut lighting on a construction site ?
max disconnection time for 110 V reduced low-voltage system ?
reasons for the use of a 20 mA RCD ?
Thanks for your fast reply!
Hi Guys,
Wonder if any of you could try and explain to me if the reason for disconnection times for fuses /proctective devices etc. As on one hand, i was told at college it is to protect the cable from catching fire etc, and then iget the impression the reason for having say 0.4 disconnection...
Hi I have a socket Radial off a 20A MCB and a lighting Radial off 6A MCB in a shed the board is fed by a 32amp MCB protected by an RCD on a TNCS syatem in the house. If I want the first point of fault ie the shed to trip first should I be using an RCBO for a TT system that trips under .2s? This...
Just
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aus
cable
circuit
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house
installation
protected
shed
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I've always wondered why BS7671 states that a disconnection time of 0.4s is required for circuits NOT exceeding 32A and for circuits exceeding 32A it is 5s
Surely you would want the higher current to trip quicker?
Can someone clarify this?
Help!
Sorry having a bad day.
I understand the concept behind touch contact of 50v and the above 1666 ohms. But when physically testing with 17th ed dilog and testing a TT system 30mA RCD. At 1x and 5X what reading would you see on your meter? or would you just test the mechanical aspect...
w crane
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rcd
rcd tripping
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testing
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tripping times
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voltage
Hello all
I no the disconnection times for TN circuits are 0.4s for final ccts with an (in) not exceedind 32A
AND 5 s
for final circuits exceeding 32A
Distrubution ccts
I have just installated some lights within a industrial building in a riser and have tested all came back ok just have...
Hi all,
Just got a query regarding what values to use from the Red Book
32a Ring Main Domestic Circuit. Do I use the 0.4s Disconnection times or the 5s Disconnection times?
regards
Tom
My uncle wants his property tested as theres a new tennant going to be moving in and just by looking at it i can see its only his sockets that have rcd protection, shower etc don't. What code does this go down as on test sheet and do they have to be changed so that all circuits are rcd...
Just had my Part P Assessment (and passed!) :)
Although I was asked one question particulat question ... so Stuart, whats the disconnection time of an S Type Circuit Breaker with timed relay. My jaw and other parts of my body hit the floor!
Funny thing is after I tried for 5 mins, he couldnt...
Stu Too
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assessment
aus
breaker
circuit
circuit breaker
disconnection
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part p
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time
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Hi
Needing help with a PIR.
1. Old wylex type 2 CBs what BS is this an what Ka rating does it have.
2. MEM Memway 3 phase DB with rewireable fuses i take it they are a BS3036
3.The Memway is fed via an 60A TPN switch fuse Oterail make would this have a BS No
4. Method of protection on PIR...
Cooker 30A I assume the disconnection time is 0.4 seconds, even though the outlet does not have a socket.
Only circuits for distribution above 32A are 5 sec.
Ta
New comer:)
Can anyone give me a quick answer on whether or not the 16th Edition permitted the non-use of RCDs for additional protection?
I've just had a call from a woman buying a house and she's described the consumer unit as having one rcd protecting cooker, shower and two socket circuits, but three...
On page 3 of schedule of inspections (where you put a tick, X or N/A in the boxes), presence of supplementary bonding conductors appears twice - once in fault protection 1) automatic disconnection of supply and again near the bottom of the page under Additional protection. Have looked in the...
pushrod
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bonding
disconnection
inspection
protection
schedule
supplementary
Guys
don't have my big read book handy at mo can you answer the following
1. 32amp circuit were protective measure against electric shock is ads is the maximum disconnection time permitted by bs 7671 = 0.5s
2. maximum Zs permitted by bs7671 for a 32amp circuit
3. What is the bs(en)...
Peter Woodford
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circuit
circuits
disconnection
domestic
fuses
maximum
would someone please explain the reasons for having a 0.4 second disconnection time and a 5 second disconnection time, why is there a big difference between the two readings :confused:
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