Zeroing fluke 1653b for testing

Hi all just a quick question to seeing if I'm doing something wrong.

When doing psc and pefc tests I'm getting fluctuating results until my meter seems to settle down. I'd carry out the tests and get 1.5ka and 1.3ka then do the same tests a few minutes later and get 1.7ka and 1.6ka which makes me think im doing something wrong.

My question is am I zeroing my meter correctly. I've set my meter to the no trip range and then I connect the 3 test leads together and keep my finger on the zero button.

Instead of the test instrument displaying 0.00 like it does when i zero it for a continuity test the display say 0.17 is this right or should it say 0.00. If that's the case do I have to deduct the 0.17 from my results when carrying out the test?

Hopefully I've not confused anyone, I just wanted to no how others zero there meter when doing a psc and pefc test.

Thanks again, chris

can't help you on this one as i use a megger. only needs leads nulling for continuity. but if you are testing at source, why use no trip?

Sorry mate it's Metrel all the way for me

telectrix said:

can't help you on this one as i use a megger. only needs leads nulling for continuity. but if you are testing at source, why use no trip?

Click to expand...

good point thank telectrix

Hi, Join the red and green leads solid jaws together, On continuity press the Zero button, The meter bleeps then press the Test button, this will zero the metre, release leads and carry out tests.

Fluke's manuals can be downloaded here:
Manuals Search

The manual implies that you should zero out all three leads for impedance/PFC tests.

I use this to null the leads before reading Zs. Home-made and approved by the assessor.

Used to have this problem with all the flukes i had until i was told how to zero it out by the guy who calibrated it for me, he said it locks itself and needs nulling before zero out.
Zero leads open first then together, works bang on after. Oh and dont let the battery voltage drop below 7.6v or its all over the place.
They eat batteries.

schoe said:

Hi all just a quick question to seeing if I'm doing something wrong.

When doing psc and pefc tests I'm getting fluctuating results until my meter seems to settle down. I'd carry out the tests and get 1.5ka and 1.3ka then do the same tests a few minutes later and get 1.7ka and 1.6ka which makes me think im doing something wrong.

My question is am I zeroing my meter correctly. I've set my meter to the no trip range and then I connect the 3 test leads together and keep my finger on the zero button.

Instead of the test instrument displaying 0.00 like it does when i zero it for a continuity test the display say 0.17 is this right or should it say 0.00. If that's the case do I have to deduct the 0.17 from my results when carrying out the test?

Hopefully I've not confused anyone, I just wanted to no how others zero there meter when doing a psc and pefc test.

Thanks again, chris

Click to expand...

Hi Chris,
1) Select your lead set, either the 3 lead set or BS1363 set.
2) Select "V" position on the rotary switch and press F3 to start a battery test, the measured battery voltage appears in the secondary display for 2 seconds, if the battery voltage is 7.2V or below replace batteries. Note: Fluke say replace at 6V but from experience this is far to low.
3) Short your lead set with the Fluke Zero Adaptor (*) that came with the MFT kit.
4)Select "Z[SUB]l[/SUB] No-Trip" or "Z[SUB]l[/SUB] Trip" as appropriate.
5)Press F1 to select "L-PE".
6)Press and hold "Zero" for more than 2 seconds until the zero annunciator appears on the display. The tester will measure and display the lead resistance, this value is then stored automatically in non-volatile memory, this is then used automatically and deducted from any subsequent loop measurement. The stored lead resistance value is available even when the MFT's power is turned off, so there is no need to re-zero the lead set each time you use the tester with the same lead set. However, if the lead set is changed for any reason (for Continuity Tests, Loop Tests or RCD Tests), the new lead set must be nulled.
* See below for details:
Somewhere in your Fluke box there should be a fancy piece of bent metal which Fluke provide as a device to aid nulling the Fluke leads. They call this expensive accessory the "zero adapter", it is provided because unlike most MFTs the 165xx series also require the BS1363 loop/RCD test lead to nulled before its use and the zero adapter allows easy shorting of the BS1363 plug pins. The zero adapter also has 3x4mm sockets to allow nulling of the red, black and green leads when used as prods or with croc-clips. Before the introduction of this device Fluke were getting a lot of complaints about inconsistent loop/RCD test results, caused by poor nulling or lack of nulling of the test leads.
Fluke zero adaptor (165xx) Part No. 3261925, £31 + VAT @1/2/2011
Fluke 165xx series MFTs are a bit temperamental when it comes to lead nulling. The manufacturers standard method is by way of the Fluke zero adaptor (provided as part of all 165xB,C&D series kits), a fancy piece of bent metal with 4mm sockets, which enables any combination of leads to zeroed reliably, even the BS1363 loop/RCD test lead. A scrap piece of 30mm wide x 50mm long copper busbar with 3 x 4mm holes in one end for nulling the 3 lead set or shorting the pins of the BS1363 plug. Alternatively 300 mm length of 1mmsq CPC wrapped round the pins of the BS1363 plug of the loop/RCD test lead are reasonable substitutes. Another method used by one of my colleges is to short the BS1363 pins on a stainless steel drainer, but it's a bit bulky to carry with you. The particularly important point is giving the croc-clips something to bite on and a method that doesn't require juggling all the leads at once.