Conduct in-service safety testing of electrical cord connect

[VK2OMD]

Recent discussion suggests that some hams might benefit from a presentation at their radio clubs on the above topic.

The content is covered in VET competency UEENEEP026A, the knowledge and skills section is quoted below.

KS01-EP026A Testing and Tagging Portable and Cord Connected Electrical Apparatus

Evidence shall show an understanding of testing and tagging portable and cord connected electrical apparatus to an extent indicated by the following aspects:

T1 Australian Standards and Commonwealth/State/Territory legislation and regulations encompassing:

Australian Standard AS/NZS 3760
Commonwealth/State/Territory Occupational Health and Safety Acts and Regulations
Limitations of work that can be undertaken
Codes of Practice and associated guidance material
Risk management principles

T2 Basic electrical testing concepts encompassing:

Basic electrical circuits
Functions of electrical circuit
Conductors and insulators
Basic electrical supply system
Relationship of electrical quantities
Effects of electrical currents
Methods/devices used to negate or minimise electrical shock
Portable Appliance Testers (PAT)
PAT maintenance and calibration

T3 Electrical equipment and cord assemblies testing encompassing:

Classification of electrical equipment
Inspection of electrical equipment (visual inspections)
Using PAT:

Earth continuity testing
Insulation resistance testing
Polarity testing (extension cords and IEC cords)

T4 Testing and tagging documentation requirements encompassing:

Risk assessment documentation
frequency of inspection and testing
tagging of equipment
records maintenance

As you can see, the competency is based on use of a PAT (Portable Appliance Tester), but the tests can be performed with a suitable ohmeter and megger. Even without a megger, the most important tests on Class 1 equipment (visual inspection and earch continuity) can be performed.

Perhaps it is an opportunity for competent hams (eg licenced electrician who understands the topic and ASNZS3760) to do a presentation to your club.

Owen

PS: this is not to suggest training in use of a PAT, but training in recognising Class 1 and Class 2 equipment, and the use of an ohmeter and megger to perform:
- Earth continuity testing
- Insulation resistance testing
- Polarity testing (extension cords and IEC cords).

[VK2JDH]

And just to add for TaT if you use a PAT you don't need to be a licensed electrician. You just need to complete a course on how to use the PAT.

[VK2OMD]

Above is an extract from the circuit of the very popular FL2100Z.

Note that it uses a two wire connection to the mains plug, the chassis is not grounded via the mains plug.

This is not a Class II (or Double Insulated) appliance, so this connection is a dangerous breach of our electrical rules, and would be revealed by a basic safety test such as done with Test 'n Tag.

My friend Tim proudly showed me his FL2100B this afternoon, same issue... 3 pin plug top with no wire on the earth pin.

So how many of these exist in the community and are traded and used without testing?

Owen

[VK5TM]

Many hundreds and probably thousands in a year.

And not only ham gear. There are thousands of other older electrical items that penny conscious people are still using, that don't meet the standards.

I used to manufacture a PAT's tester for an Adelaide company and still do the repairs and calibration on them.

How some of the people doing the testing and tagging passed their training course is beyond me, the damage I have seen some do to their equipment.

[VK5ZD]

My friend Tim proudly showed me his FL2100B this afternoon, same issue... 3 pin plug top with no wire on the earth pin.

Just checked the FL-2100B I've got here; earth pin on the plug is connected to the chassis.

[VK3ZAZ]

And just to add for TaT if you use a PAT you don't need to be a licensed electrician. You just need to complete a course on how to use the PAT.

The course leads to the issue of a licence in this state.

Without a lic you cannot tnt pubic places..

NSW got their ambiguous tag colour codes sorted yet?

[VK3ZAZ]

Many hundreds and probably thousands in a year.

And not only ham gear. There are thousands of other older electrical items that penny conscious people are still using, that don't meet the standards.

I used to manufacture a PAT's tester for an Adelaide company and still do the repairs and calibration on them.

How some of the people doing the testing and tagging passed their training course is beyond me, the damage I have seen some do to their equipment.

Did you see the story about the woman who died using a mobile phone plugged into a plug pack s/m wall charger?

Sad case.

And also hm guys get their PATs recalibrated every 12 months?
Or have legal tags with their lic number on.

One coy here makes their own illegal labels no standard and no lic number

another just does visual inspection and tags the racks full of IEC leads cable tied so hard ypu can see the cut marks in the outer sheath,,
arguing that if nothing LOOKS changed then its still in compliance...

LOL

[VK3ZAZ]

Screenshot - 02_07_2014 , 17_24_41.png

Above is an extract from the circuit of the very popular FL2100Z.

Note that it uses a two wire connection to the mains plug, the chassis is not grounded via the mains plug.

This is not a Class II (or Double Insulated) appliance, so this connection is a dangerous breach of our electrical rules, and would be revealed by a basic safety test such as done with Test 'n Tag.

My friend Tim proudly showed me his FL2100B this afternoon, same issue... 3 pin plug top with no wire on the earth pin.

So how many of these exist in the community and are traded and used without testing?

Owen

Most of the jap crap back in 80s like metal rotor boxes keyers had this its the JA way of accommodating international voltage standards trouble is 117 plus 117 is 234 last count and we are way overe that 240-258 seen often

half the stuff in ham shacks prob doesn't comply

On our sites ALL 200V stuff like tandbergs have ARLEC step down transformers as a legal requirement

all NEC transmitters have voltage regulators 240 to 200 v.

I am amazed that the resellers of FL2100 and the like were able to sell non compliant power supplies.

Some however like the HAM rotors pulled out all the AC input at one stage and offered only 28VAC they were so afraid they might kill someone and be liable.

I also wonder if testers and people realise for example if you own an extension lead and loan it to someone and its faulty and they get injured or killed you the owner are responsible for that death as owner of the tested lead?

[VK2OMD]

Just checked the FL-2100B I've got here; earth pin on the plug is connected to the chassis.

Not just connected, it should have a resistance from earth pin on the plug top to any exposed metal of not more than 1 ohm.

If testing insulation resistance, for a Class 1 appliance (except for MIMS elements like electric fry pans), minimum resistance is 1M ohm (power switch etc ON of course).

The latter might condemn some aged equipment that has suffered the effects of moisture over time.

Owen

[VK5ZD]

Not just connected, it should have a resistance from earth pin on the plug top to any exposed metal of not more than 1 ohm.

My apologies. In my book, 'connected' means they are joined together. If there was some resistance in the path I would have said so

[VK2JDH]

you own an extension lead and loan it to someone and its faulty and they get injured or killed you the owner are responsible for that death as owner of the tested lead?

For items in a domestic environment TaT is not a requirement.

[VK5TM]

And also hm guys get their PATs recalibrated every 12 months?
Or have legal tags with their lic number on.

SA OH&S (or whatever they call themselves these days) says they have to have the calibration checked every 12 months and tags must be such that they are readable in 12 months time, as well as license number.

For items in a domestic environment TaT is not a requirement.

Yet. Once they work out how to make you do it and tax you for doing it or fine you for not doing it, it will be on.

[VK6ZFG]

I came across a heavy duty orange extension lead with the original factory installed molded plug and socket.

The plug was in a bad state and needed a fix.

On inspection the lead was found to only have two conductors with no earth conductor at all included in the lead! From what I could work out this extension lead was from before the introduction of RCDs!

Only testing would have revealed this deficiency.

[VK5TX]

Just because it has been tagged doesn't mean it's safe!!!

10A to 15A

[VK2OMD]

Another of these cases that would be exposed if hams took the trouble to perform or have performed tests similar to those prescribed for Test 'n Tag...

Above, the power supply schematic for the Yaesu FL1000. Note that there is no connection to a power cord earthing conductor shown. (This was the American and Japanese way back then.)

Also relevant is that the diagram they give showing how to connect up a receiver, transmitter, and amplifier does not show any protective earth connection... so if you used their manual, the equipment chassis are effectively bonded together by the coax shields but not connected to the supply earth system.

So, consider the consequence of c18 or c19 failing s/c or even just very leaky... the whole station chassis could have dangerous voltages (up to mains voltage) on it, and possibly the antenna system.

Above is the output end of this amplifier, the left hand connections go to the valve anodes and have HV applied whenever the power is switched on. Consider C14 failing s/c or even just leaky... it permits the centre of the coax to reach +HV (~900V) wrt chassis, and if the coax centre was grounded in the antenna system but the shield was not, the station chassis could reach dangerous potentials (up to 1kV).

This stuff did not comply with our safety rules at the time, and still doesn't, but there are probably many of these in service and being sold as 'working' today.

The skills and knowledge to competently test this stuff, and the thorougness to perform or have performed the tests might prevent an adverse outcome for some ham, member of his family, or someone else.

Owen

PS: good designs, and the FL1000 is NOT, put a substantial RF choke in shunt with VC2 to prevent c14 faults causing high voltage DC on the antenna connector. This matter was discussed here some time ago where it became apparent that some Australian manufactured amplifiers did not include such protection.

[VK2OMD]

I have written some notes on earth continuity testing of equipment based on AS/NZS 3760:2010 In-service safety inspection and testing of electrical equipment at http://owenduffy.net/blog/?p=2202 .

Owen