2391 Practical Exam!

[gsparks101]

Hi ive got my 2391 practical coming up and know i will be taught on the day on what to test for but would be very happy if someone could give me a quick run down. i know there's the small tests of the 12Visual inspection, Insulation Resistance test, Live Loop impedance Test so im all right with those and what to do but for the final board. Am i meant to do all those tests aswell? this is what i was told my board would be like please just give me a quick follow through just in case.

1L1 Subman DB2
1 L2 Ring Final
1L3 Radial-MICC
2L1 Spare
2L2 Spare
2L3 Spare
3L 1 3 Phase Motor Starter

For each one of them do i do the Continuity test, Insulation Resistance, Polarity and Earth loop impedance????????? would there be any need to do anything else? AND what does SPARE mean? is that just the incoming supply or what :s AND the 3 Phase Motor does that just get tested as you would test at a 3 Phase DB? at each points and then themselves and vice versa???

Anyway thank you for any who posts it will be a great deal of help to me

Regards Guj

 

[flameport]

You do all of the required tests using the order and process described in GN3. Repeat for all of the circuits.
This includes all the tests you have listed, and the other ones you have forgotten.

The reason for there being different types of circuit in the board are that the tests required and how they are carried out will be different for each one.

Spare means spare. As in not used.

Not sure what you mean by 'just get tested as you would test at a 3 Phase DB' - the board as described is obviously a 3p one anyway.

 

[gsparks101]

oh ok i see now thanks! i think i was just confusing myself abit as i haven't worked on a 3 phase board yet. Each test would be similar to any other test even for the 3 phase Motor. So for the continuity test for the motor would you do end to ends test? or would you make a link in the DB. i assume for some reason you do the ends tests :s but then again what do i know

 

[Jaymack]

Your tutor should have explained the procedure for Zs at a motor and you should have a copy of Guidance Note 3. The loop impedance for a motor circuit is carried out at the supply side of the isolated motor control gear. The continuity of the CPC and motor are also required.

Regards

 

[RF Lighting]

C.R.I.P.P.L.E

 

[holmslaw]

..

 

[ColJack]

so bear with me..

C - Continuity of earths / CPC's including bonding
R - Ring Continuity
I - Insulation resistance
P - Polarity
P - Power up???? or polarity after power up..
L - Loop impedance ( including earth electrode if needed )
E - Evrything else? ( PFC / RCD tests.. )

?????

 

[Taylortwocities]

E = Energised tests?: Zs, RCD, functional

 

[ban-all-sheds]

This gets most moronic post of the week award.

That's unusually self aware of you.

 

[Electrifying]

C.R.I.P.P.L.E

Not applicable - the 'main board' section of the 2391 practical is a PIR.

You can do the testing in any order that you see fit.

For example:

Safe Isolation

Polarity of supply

PFC

Ze

Continuity of protective conductors

RFC continuity

IR

Polarity

Energise

At sub-board .... PFC and Zs(Zdb)

Zs

RCD and Functional

Phase rotation and Voltage drop - if required.

 

[Cremeegg]

You need to know the tests well before the practical exam. I'm surprised you'd be told what to test. You need to know and demonstarte clearly the principles and practice of safe isolation with the 3P DB. Also how to test starters, motors, contactors, MICC, two way switching, intermediate switching, dimmers, a 1P board and RCD's. If I remember my 2391 correctly.

Frankly I'm surprised you passed the theory asking questions like this; but they dont let you progress to the practical unless you have passed the theory - so well done for that bit.

Looks like you have plenty to learn and you need to be pretty quick around the boards as well - and know how to fill in the forms as well - and lastly know how to use your own meter or pray that you can use one at the centre correctly.

Good luck - I've a feeling you might need it - overall pass rate is around 45%.

 

[Risteard]

but they dont let you progress to the practical unless you have passed the theory - so well done for that bit.

Not correct. Many do practical whilst they are awaiting results of theory. However the Certificate is only awarded once both parts have been successfully completed.

 

[Spark123]

We did the practical first, followed by a 3 month wait for the written exam

 

[ban-all-sheds]

Good luck - I've a feeling you might need it - overall pass rate is around 45%.

//www.diynot.com/forums/viewtopic.php?t=234443

 

[Taylortwocities]

We did the practical first, followed by a 3 month wait for the written exam

Followed by a 3-month wait for the result, followed by a 2-month wait for the certificate.