Search found 919 matches
- Wed Dec 14, 2022 9:48 am
- Forum: Earthing and Bonding
- Topic: MEC sized by max demand
- Replies: 7
- Views: 9352
Re: MEC sized by max demand
Basically you're saying that the MD is 40 A (I assume per phase, since it's a block of flats); and based on that the mains size only needed to be 10 mm2 - therefore allowing use of 4 mm2 MEC. So the question becomes: can you validly claim the mains conductors have been increased in size to deal with...
- Sat Dec 10, 2022 10:14 am
- Forum: Appliances
- Topic: Single Phase Welders, let's get to the bottom of this
- Replies: 7
- Views: 8188
Re: Single Phase Welders, let's get to the bottom of this
I expect that tally-plate rating of 14.4 A will be the max continuous load, ie at 100 % duty cycle. The unit won't be able to draw 23.8 A continuously. I don't believe that's valid; should be the actual max load for normal operating. Excluding inrush /start / arc-striking currents; so equivalent to ...
- Sat Dec 10, 2022 10:01 am
- Forum: Off Topic/General Electrical Discussions
- Topic: EWRB COC Audits?
- Replies: 2
- Views: 5061
Re: EWRB COC Audits?
Since CoC forms are no longer issued by EWRB, and are not required to have a serial number (or any other form of unique ID);
EWRB can't tell how may CoCs any practitioner, has purchased / issued.
They still have the power to request copies, and so can audit, but seem not to do so as routine.
EWRB can't tell how may CoCs any practitioner, has purchased / issued.
They still have the power to request copies, and so can audit, but seem not to do so as routine.
- Thu Dec 08, 2022 10:34 am
- Forum: Protective Devices
- Topic: RCD/RCBO where not to use / nuisance tripping
- Replies: 2
- Views: 4673
Re: RCD/RCBO where not to use / nuisance tripping
You should have no problem with any of those. so-called 'nuisance tripping" is almost always caused by poor selection and / or installation; especially standing leakage; including - capacitance of cables - having too many appliances on same RCD (especially switch-mode power supplies). When RCDs firs...
- Wed Dec 07, 2022 5:49 pm
- Forum: Switchboards
- Topic: Top or bottom feed
- Replies: 1
- Views: 3406
Re: Top or bottom feed
There used to be a requirement to have either all-top or all-bottom (a long time ago); but it wasn't really practicable then and certainly isn't now. Nor is it based on any particular safety outcome; just what could be called "good practice". Most domestic (and similar ) switchboards will top-feed t...
- Wed Dec 07, 2022 12:54 pm
- Forum: Inspection
- Topic: Inspection of non-accessable items
- Replies: 4
- Views: 5390
Re: Inspection of non-accessable items
What it takes to "satisfy" any Inspector is up to that Inspector. Personally I'd expect a minimum of photographic evidence from anyone i didn't already have a high level of trust in. When you issue an RoI that says "it complies, and will be safe when enlivened"; you're formally accepting responsibil...
- Tue Dec 06, 2022 5:52 pm
- Forum: Appliances
- Topic: Single Phase Welders, let's get to the bottom of this
- Replies: 7
- Views: 8188
Re: Single Phase Welders, let's get to the bottom of this
the adapter cords you describe are electrically unsafe; because they can have 15 A pf load applied when the plug is only rated 10 A.. Would be OK if they had an in-line mcb to limit the current. Which takes care of the issues arising from carrying the welder (or whatever) around a variety of custome...
- Fri Dec 02, 2022 4:01 pm
- Forum: Transportable Installations
- Topic: Tiny Home WoEF renewal
- Replies: 8
- Views: 6908
Re: Tiny Home WoEF renewal
I agree.
My previous comment wasn't intended to cover leases / rentals
My previous comment wasn't intended to cover leases / rentals
- Fri Dec 02, 2022 8:47 am
- Forum: Standards and Legislation
- Topic: DR AS/NZS3017
- Replies: 5
- Views: 6221
Re: DR AS/NZS3017
"timing is everything"
- Thu Dec 01, 2022 4:43 pm
- Forum: Transportable Installations
- Topic: Tiny Home WoEF renewal
- Replies: 8
- Views: 6908
Re: Tiny Home WoEF renewal
technically this only works uf the CI is never unplugged.
Though how the powers-that-be would ever know about that ....?
Though how the powers-that-be would ever know about that ....?
- Thu Dec 01, 2022 4:41 pm
- Forum: Transportable Installations
- Topic: Tiny Home WoEF renewal
- Replies: 8
- Views: 6908
Re: Tiny Home WoEF renewal
Spakznz is correct.
The requirement for WoEF applies only when it is proposed to connect to supply.
The obligation is on the person allowing connection,not on the CI owner.
The requirement for WoEF applies only when it is proposed to connect to supply.
The obligation is on the person allowing connection,not on the CI owner.
- Thu Dec 01, 2022 4:38 pm
- Forum: Standards and Legislation
- Topic: DR AS/NZS3017
- Replies: 5
- Views: 6221
Re: DR AS/NZS3017
3017 has been published; and can be purchased
But not yet available via EWRB
But not yet available via EWRB
- Thu Dec 01, 2022 4:34 pm
- Forum: General Electrical Discussions
- Topic: Strip Connector Busbar?
- Replies: 3
- Views: 4591
Re: Strip Connector Busbar?
most brands of rail-mount terminals will have similar.
Finding something to fit a standard "strip" of non-rail connectors will be trial & error.
Finding something to fit a standard "strip" of non-rail connectors will be trial & error.
- Thu Dec 01, 2022 4:31 pm
- Forum: Transportable Installations
- Topic: 3001: 2022 edition
- Replies: 4
- Views: 6304
3001: 2022 edition
new 2022 edition of "3001" was published mid Nov. So far only Part 1 is showing on SNZ website via EWRB link, but both parts are there of you go directly to SNZ. This will be a glitch in the deal between EWRB & SNZ There are a few changes to part 1 (site supplies); and a lot of changes to part 2 (co...
- Fri Nov 11, 2022 12:03 pm
- Forum: Selection and Installation of Wiring Systems
- Topic: Fixed space heating max demand
- Replies: 1
- Views: 3215
Re: Fixed space heating max demand
you have plenty of choice about how you determine MD [2.2.2]. Whatever you decide it us; you then select cable size to carry it; and you protect that cable against overcurrent. Which is essentially determining MD by "limitation". Therefore MD is not an (electrical) safety consideration; so the point...
- Mon Nov 07, 2022 10:59 am
- Forum: Generators and Solar
- Topic: Inverter and battery in the bedroom
- Replies: 2
- Views: 5141
Re: Inverter and battery in the bedroom
Yes. AS/NZS 5139 says BESS shall not be located in habitable rooms of domestic / residential installations. 4.2.2.2 for pre-assembled BESS 6.2.2.2 for other BESS Not just a recommendation; but "shall not". This is the only installation Standard that covers lithium batteries. Compliance is required b...
- Fri Nov 04, 2022 7:21 pm
- Forum: Inspection
- Topic: ROI for two COCs
- Replies: 1
- Views: 3040
Re: ROI for two COCs
There is no reason an RoI cant relate to work done on more than one CoC,
provided all the (high risk) work relates to installation at same location
provided all the (high risk) work relates to installation at same location
- Wed Nov 02, 2022 12:37 pm
- Forum: Selection and Installation of Wiring Systems
- Topic: 3.11 Underground Wiring Systems - Ducts
- Replies: 3
- Views: 4811
Re: 3.11 Underground Wiring Systems - Ducts
Depends in the basis of the claim of the duct being "HD". I'm no expert on details of the manufacturing standards that apply; but I see no reason a duct (ie > 75 mm) could not be manufactured to comply with a conduit Standard. In which case I'm sure that fact would be clearly marked on it - as eithe...
- Wed Nov 02, 2022 11:38 am
- Forum: Earthing and Bonding
- Topic: Bonding
- Replies: 3
- Views: 4164
Re: Bonding
Good thought, and I probably should have thought more about the fact that you're planning to use a socket. If someone does plug another Class I appliance into this socket, there will be greater risk of different earth potentials. Not just earthed items within arm's reach of the pump, but earthed ite...
- Tue Nov 01, 2022 12:33 pm
- Forum: Earthing and Bonding
- Topic: Bonding
- Replies: 3
- Views: 4164
Re: Bonding
Correct that there is a risk of touch voltages. Most obviously an earth fault in the pump motor will result in high current flowing in the PEC of the pump circuit. The pump motor will therefore have a voltage higher than the MEN point of the house, due to impedance in the PEC. The value could be sig...
- Tue Nov 01, 2022 12:04 pm
- Forum: Selection and Installation of Wiring Systems
- Topic: 3.11 Underground Wiring Systems - Ducts
- Replies: 3
- Views: 4811
Re: 3.11 Underground Wiring Systems - Ducts
Duct is a term defined in "3000" [1.4.42]. Basically something intended to have cables drawn in. Conduit is a form of wiring enclosure, and is generally part of a "wiring system" refer 3.2 & Table 3.1. The terms are not synonyms; but also not exclusive. Conduits less than 75 mm cannot be ducts (by d...
- Fri Oct 28, 2022 10:25 am
- Forum: Selection and Installation of Wiring Systems
- Topic: What defines something as telecommunications?
- Replies: 3
- Views: 4857
Re: What defines something as telecommunications?
Hard to understand how wiring within a switchboard could be regarded as anything other than a "wiring system". The term "wiring systems" is defined in 2018 edition. For purposes of 2007 edition; the meaning has to be interpreted . Partly from the way the term is used in Section 3; particularly the f...
- Wed Oct 26, 2022 1:32 pm
- Forum: Selection and Installation of Wiring Systems
- Topic: Fibre segregation
- Replies: 1
- Views: 3526
Re: Fibre segregation
yes it needs to follow the same rules. Or rather, we need to follow the same rules in "3000" WRT fibre as WRT other telecomms wiring. So 3.9.9.8.4 for spacing still requires us to follow TCF rules (which may have different, requirements WRT fibre than eg UTP / STP) 3.9.8.3 is unlikely to apply, as t...
- Wed Oct 26, 2022 1:26 pm
- Forum: Selection and Installation of Wiring Systems
- Topic: What defines something as telecommunications?
- Replies: 3
- Views: 4857
Re: What defines something as telecommunications?
the requirements of 3.9.8.4 are about interference. 3.9.8.3 is about voltage / insulation. Both are in Section 3, so apply to "wiring systems". wiring within an equipment enclosure, eg swbd / control panel, is also "wiring systems". so these rules still apply; however the details of how they apply w...
- Wed Oct 26, 2022 1:04 pm
- Forum: Testing & Verification
- Topic: Best way to confirm correct circuit connections?
- Replies: 8
- Views: 10270
Re: Best way to confirm correct circuit connections?
I (carefully) didn't say "having the MEN open is key"; I said having the N-E loop open is key. Which may be by opening the MEN, or by disconnecting the circuit N (but generally should not be achieved by disconnecting any PECs). Unless we take this step, we can't eliminate possibility of N-E reversal...
- Tue Oct 25, 2022 1:56 pm
- Forum: Standards and Legislation
- Topic: ESR59 - Replacement
- Replies: 1
- Views: 3709
Re: ESR59 - Replacement
very good question. There's certainly no definitive ruling to be found in the ESRs. The answer is up to each of us; we need to be prepared to justify our decisions - and may find that others disagree. "Original condition" is a matter of interpretation; but it's certainly NOT restricted to being exac...
- Tue Oct 25, 2022 12:31 pm
- Forum: Transportable Installations
- Topic: Tiny home 32A app inlet and supply
- Replies: 2
- Views: 3913
Re: Tiny home 32A app inlet and supply
Correct. What this doesn't allow is - for example - a 10 A rating, even for very low-power units. Or a 16 A "3123" type (no idea why not). Interestingly, under 1976 Regs, a 10 A plug could be used (under certain conditions, as per the official newsletter dated Aug 1992); and any built that way can r...
- Tue Oct 25, 2022 12:10 pm
- Forum: Testing & Verification
- Topic: Best way to confirm correct circuit connections?
- Replies: 8
- Views: 10270
Re: Best way to confirm correct circuit connections?
yes, I missed that you have the N disconnected for the ECC test. Which is the equivalent of having it connected, but MEN open. In that case, yes the ECC testing shows PECs correctly connected at all points along circuit (as well as confirming the PEC part of the EFLI (which for many circuits is enou...
- Sun Oct 23, 2022 2:17 pm
- Forum: Testing & Verification
- Topic: Best way to confirm correct circuit connections?
- Replies: 8
- Views: 10270
Re: Best way to confirm correct circuit connections?
Yes there is some logic to treating "correct circuit connections" as being part of "polarity". But there are aspects of ccc that have nothing whatever to do with polarity. So the change (in A1 to 2018, not in original 2018) makes some aspects more logical; but risks causing other confusions. As Doug...
- Tue Oct 18, 2022 11:00 am
- Forum: Electric Vehicles and Charging Systems
- Topic: Direct coupled solar panels
- Replies: 1
- Views: 4291
Re: Direct coupled solar panels
Not really relating to electric vehicles... Using d.c from PV to heat water is not new; but there are several fish-hooks. The load is just a resistance (around 18 ohms), so the variable voltage from unregulated PV will simply result in varying current / power. So as long as the resistance is selecte...
- Wed Oct 12, 2022 10:49 am
- Forum: Distribution, Networks & Metering
- Topic: Auditing Network works
- Replies: 1
- Views: 4432
Re: Auditing Network works
A PL (or other authorisation) is required , by the Act, for PEW (unless an Exemption applies). Also required, by ESRs, for some non-PEW; like issuing WoEF and some types of periodic assessment. PEW as defined in Schedule 1 basically includes installation, connection, or maintenance of fittings / con...
- Mon Oct 03, 2022 10:35 am
- Forum: Standards and Legislation
- Topic: Certification in large industrial situations
- Replies: 2
- Views: 3154
Re: Certification in large industrial situations
That makes sense, and is permitted under ESR 74E as alternative to the default of providing to the person to contracted for the work. Literally, this option is only available if the person to contracted for the work is not "readily available"; so if you can identify who asked for the work to be done...
- Fri Sep 30, 2022 3:23 pm
- Forum: Standards and Legislation
- Topic: Employer held responsible for workers transposition
- Replies: 3
- Views: 4601
Re: Employer held responsible for workers transposition
Not the first time Worksafe have preferred to use HSW law rather than electrical law. And won't be the last. Quite simply, it's far easier for them to get a conviction that way; because the burden of proof is reversed. There's no such principle as innocent until proven guilty. In stead you're presum...
- Tue Sep 27, 2022 9:59 am
- Forum: Standards and Legislation
- Topic: Type of supply system for CoC
- Replies: 3
- Views: 4408
Re: Type of supply system for CoC
The type of supply system is about what form of earthing is used. It's generally "MEN"; because that's what's normally used for both distribution and installations in NZ. MEN is the particular variant of TN-C-S used in NZ (and Oz). TN for "terra neutral"; ie the neutral is earthed; and -C-S designat...
- Tue Sep 27, 2022 9:45 am
- Forum: Standards and Legislation
- Topic: ROI - who to give the copy too?
- Replies: 1
- Views: 2787
Re: ROI - who to give the copy too?
The wording of ESR 72A requires a copy of the RoI to be provided (not "given") to " the person who contracted for the prescribed electrical work". ESR 74E uses similar wording: "the person who contracted for the work" for a copy of CoC. And ESR 74G reverts to " the person who contracted for the pres...
- Mon Sep 26, 2022 7:59 pm
- Forum: Standards and Legislation
- Topic: Who can "assess" PEW in regards to ESR 75 (2)?
- Replies: 2
- Views: 2992
Re: Who can "assess" PEW in regards to ESR 75 (2)?
Short answer is "No". That's because there authorisations to do various kinds of PEW are specified in the 'limits of work' set by EWRB for each class of PL. And none of them authorise "assessment" of anything. If you look at the history; ESR 75 used to sat "inspect"; which was changed in 2013 to "as...
- Fri Sep 23, 2022 8:33 am
- Forum: Standards and Legislation
- Topic: How long do we have to issue a CoC?
- Replies: 14
- Views: 8157
Re: How long do we have to issue a CoC?
Working Days will have been a deliberate choice; allows for not only weekends but also public holidays.
I suspect they fixed on 20 WD as a standard length of time, being essentially 4 weeks in normal circumstances (a "working month?).
I suspect they fixed on 20 WD as a standard length of time, being essentially 4 weeks in normal circumstances (a "working month?).
- Thu Sep 22, 2022 6:51 pm
- Forum: Standards and Legislation
- Topic: How long do we have to issue a CoC?
- Replies: 14
- Views: 8157
Re: How long do we have to issue a CoC?
Yes; CoC must be issued before connection? Issuing of the CoC completes the work; which starts the 20 WD timer. Yes; technically an offence to connect first and issue CoC after. And as you say, this is what happens most of the time. ---------- The legal driver for issuing CoC is that the work must n...
- Wed Sep 21, 2022 9:40 am
- Forum: Selection and Installation of Wiring Systems
- Topic: ECP34 vs 3000
- Replies: 2
- Views: 3993
Re: ECP34 vs 3000
There is no conflict. The relevant definitions are in the Act. "Installations" that have a "point of supply" (PoS) start at the PoS; which is generally where conductors that are supplied from a network cross the property boundary. "Lines" are part of "works" so are external to the PoS. For aerial su...
- Wed Sep 14, 2022 10:20 am
- Forum: Selection and Installation of Wiring Systems
- Topic: Replacing 10A with 15A socket
- Replies: 2
- Views: 5880
Re: Replacing 10A with 15A socket
Agree. Overcurrent protection is primarily about the cable. We select cable to carry the expected current; and then protect it so it can't be made to carry loads in excess of the as-installed CCC. Only in a dew special cases is overcurrent protection required for other fittings in the circuit; eg in...
- Mon Sep 12, 2022 5:07 pm
- Forum: Damp Situations
- Topic: exhaust fan in shower
- Replies: 9
- Views: 10118
Re: exhaust fan in shower
That's a valid answer; just not to any question that was asked in this thread.
- Mon Sep 12, 2022 10:48 am
- Forum: Transportable Installations
- Topic: Can a transportable structure have a 10A appliance inlet?
- Replies: 1
- Views: 3633
Re: Can a transportable structure have a 10A appliance inlet?
I presume you're asking only WRT land-based CIs; complying with "3001". clause 3.2.2 specifies the permitted types of appliance inlet, but does not set a minimum rating for this fitting. However 5.1.2 specifies the permitted types of fittings that can make up the supply lead, including the connector...
- Thu Sep 08, 2022 10:35 am
- Forum: Generators and Solar
- Topic: Best Practice earth loop impedance B type C/B or fuses
- Replies: 7
- Views: 7155
Re: Best Practice earth loop impedance B type C/B or fuses
You'll need to check that the fuse (or mcb) will operate within 5 sec with only 40 A available (compared to the typical 1kA we can expect with a grid supply). Not sure how easy it will be to get detailed info on operating curves for fuses. Personally I'd just use an RCD. For a 30 mA RCD; tripping wi...
- Wed Sep 07, 2022 10:07 am
- Forum: Generators and Solar
- Topic: Best Practice earth loop impedance B type C/B or fuses
- Replies: 7
- Views: 7155
Re: Best Practice earth loop impedance B type C/B or fuses
The alternative is to rely on 7.3.5.2.1; and ensure the conductors of the non-RCD circuits have a CCC at least as high as the inverter peak output.
That's peak output, not rated output.
That's peak output, not rated output.
- Wed Sep 07, 2022 10:04 am
- Forum: Generators and Solar
- Topic: Best Practice earth loop impedance B type C/B or fuses
- Replies: 7
- Views: 7155
Re: Best Practice earth loop impedance B type C/B or fuses
Using B-curve mcbs instead of C-curve lakes a difference only of the supply source us capable of providing the high current necessary for an over-current device. Yes Tables 8.1 & 8.2 allow for a higher impedance ; but they are based on a normal (ie grid) source. They are not relevant for low-capacit...
- Wed Sep 07, 2022 9:52 am
- Forum: Damp Situations
- Topic: exhaust fan in shower
- Replies: 9
- Views: 10118
Re: exhaust fan in shower
No, that's not what the Note means at all. Table 6.1 sets out the rules for various types of equipment in each Zone; although the actual requirements are on the respective clauses. Step 1: establish the Zones for the particular case. While the Figs help; always check by reading the relevant clause; ...
- Tue Sep 06, 2022 5:20 pm
- Forum: Generators and Solar
- Topic: Best Practice earth loop impedance B type C/B or fuses
- Replies: 7
- Views: 7155
Re: Best Practice earth loop impedance B type C/B or fuses
In normal grid-supplied circuits we typically use one over-current device to perform 3 different functions. First is overload protection of the conductors, , quite straightforward. Next is short circuit protection, again to protect conductors. Time requirements as per 2.5.4.5 When using a genset or ...
- Tue Sep 06, 2022 4:48 pm
- Forum: Damp Situations
- Topic: exhaust fan in shower
- Replies: 9
- Views: 10118
Re: exhaust fan in shower
the fact that a wall limits the Zone means that if the (whatever) is inside the wall, that limits the Zone, then it's not in the Zone. But an extract fan won't be installed inside the wall, it is mounted - at least partially - on the wall, and that part of it is in the zone. Z 1 for a water outlet o...
- Mon Aug 29, 2022 7:36 pm
- Forum: Transportable Installations
- Topic: Volt drop in connectable installations?
- Replies: 3
- Views: 4305
Re: Volt drop in connectable installations?
There's an Exception, bit basically today's caravans/ motorhomes use ELV d.c. or lightoing, and LV circuits are generally sockets / appliances
- Mon Aug 29, 2022 11:26 am
- Forum: Transportable Installations
- Topic: Volt drop in connectable installations?
- Replies: 3
- Views: 4305
Re: Volt drop in connectable installations?
A "connectable installation" is, always, supplied from a point in an "electrical installation" - generally a socket outlet. The volt drop limits of "3000" apply to the socket outlet the CI plugs into (and "3001" provides guidance for estimating max demand within a caravan park). No allowance / corre...