in this presentation we look at the need to use a torque screwdriver when reconnecting conductors
have been disconnected from a distribution board in order to comply with the IET and in this case
the manufacturer being Crabtree requirement to get into the right Newton meter of torque
at terminating points at the top of breakers for neutral bars and the main switch so they
see how we're going to conform with that we can see in the literature have given to us with the
distribution board the manufacturer is set the Newton meters of torque required for the main
switch the MCB's and the earth and neutral terminals and these were what we'll be using
during this presentation we will also require a calibrated torque screwdriver this screwdriver
will incorporate a plus/minus head and not a pozi drive screwdriver head so what's happened
then is we've come along with perhaps tests in a circuit in this case I've disconnected
the lighting circuit i have performance and tests on it and we need to re terminate them both into
the earth bar the neutral bar and into the top of the breaker and we'd like to think that when the
installation was installed that the terminations are set to the correct torque rating when they
were terminated and now we've got to also repeat that process when reconnecting them back into the
distribution board itself it's not acceptable to use a standard pozi drive screwdriver for
the type of terminations in the earth bar neutral bar on the top of the breakers we
should be using a plus/minus driver in order to get the correct connection on top of the screw
head before we tighten it up okay and then we need to also set this to the appropriate torque
rating comparing it to the requirements for the earth bar neutral bar and the top of the breaker
they are not all the same so in order to make the terminations into the earth and neutral bar
and need to set my torque screwdriver driver to 1.7 Newton meters so for the screwdriver
with a plus/minus head on it and I get the talk adjuster out I need to rotate the number round
until I get to 1.7 however the screwdriver doesn't show 1.7 I need to set it between
1.6 and 1.8 which is a blank white screen in order to get to 1.7 Newton meters with the
torque setting of 1.7 Newton meters removed the adjuster and reinsert the plus/minus driver and
now we're ready to use it from the distributions earth and neutral bars so we've consulted with
the manufacturer's instructions and seen we need 1.7 Newton meters of torque in order to connect
into the earth and neutral bar in my torque screwdriver set up and let's see how that's
going to look in semiconductor into the terminal is my plus/minus driver and then I'm up to the
appropriate 1.7 Newton meters we hear that screw drivers made it click that's at the right torque
setting we move across the neutral bar and repeat the process for the neutral conductor as well so
once again 1.7 Newton meters of torque onto the neutral bar and again click to suggest we're at
the correct torque setting next after consulting the manufacturers instruction for the star breaker
Crabtree dis board I need to set it to 2.2 as I have done Newton meters of torque in order
to connect the connection to the top of the 6 amp circuit breaker so again connection comes
in torque screwdriver until we hear a click and therefore we're at the right torque setting of
2.2 Newton meters for the top of the circuit breaker I'm in the distribution board we look
at the torque setting required for the top of the main switch the linked main switch or double pole
switch and the top of the RCCB's the Newton meter torque setting for those is 2.3 Newton meters
I've set my torque screwdriver up and let's see if they are torqued up correctly correct
so can now see the requirements for both the connections into the earth bar the neutral
bar of top of the circuit breakers and main switching are RCCB's require from manufacturers
and the IET to be set to the appropriate manufacturers torque setting in Newton meters