RCD Testing

DanBrown · Mar 28, 2009

When it comes to testing an RCD typical 30mA standard what are the appropriate test to do.

The way i thaught is;
1 - Functional via Test button
2 - 1/2 times test = no trip on 0 degrees
3 - 1/2 times test = no trip on 180 degrees
4 - 1 times test = trip at max 300mS on 0 degrees
5 - 1 times test = trip at max 300mS on 180 degrees

What i cannot unerstand is, when does the RCD ramp test be used? to see if it does trip within 30mA,
also when does the 5 times trip current be performed?

Thanks

Spudnik · Mar 28, 2009

1/2 times - 0 & 180 deg.
1 times - 0 & 180 degrees - record highest value
5 times 0 & 180 degrees - record highest value

Functional test with trip button.

x1 200ms max
x5 40ms max.

Ramp test is generally only used to fault find and to test the RCD tripping current.

Mr Mark Sparks · Mar 28, 2009

i use the ramp to see how many m/a are tripping an rcd if it has been going out for what seems like no reason and all other tests are ok, also the 5x test is always part of my testing, mft 1552 does it on auto test anyway

DanBrown · Mar 28, 2009

Can you just confirm the 200mS, as ive found it to be 300mS, Page 92 of OSG..
Also when it comes to the EIC sheet, it says RCD time.. Obviously you put in max time, but for what test - at 1 times?

Thanks

Spudnik · Mar 28, 2009

Havent got my OSG to hand at the mo. I think it used to be 300 or am i just making this up?

What certs are you using?

DanBrown · Mar 28, 2009

The RCD trip time for a general purpose RCCB to BS 4293 states that at 1 times, should be less than 200mS, but
over the page says for general purpose RCCB to BS EN 61008 and RCBO's to BS EN 61009 is 300mS. I thaught thats these were the standard type, but might be wrong.

As far as the certs are concerned i was referring to the one's in the big red book, standard one's.. What does NIC ask on ther's?

Thanks

Guest123 · Mar 28, 2009

Hey.

In ol' red the 1 x is 300mS
the 5 x is 40mS

Usually you put The 1x reading down (on the middle page of an NIC domestic).

Spudnik · Mar 28, 2009

Ah, fair enough chaps. 300ms.

Still as least i know mine all come in under 200

As for the NIC certs, i thought there were test time columns for x1 and x5 at the end of each row?

Guest123 · Mar 28, 2009

There are on the test results sheet, last page.

I thought he meant on the middle page where it asks for characteristics if an RCD is used as a main switch.

To coin a phrase.....I'll get me coat.