IEC 60077-1 1220VAC hipot test

[woodford]

I have to test a cable harness at 1220 VAC and need to understand more about what is being requested so I can purchase the correct equipment. the customer has requested 2M Ohms at 1000 VDC and 1220 VAC according to IEC 60077-1. This is how I see what is requested: Test one use a MEGGER at the requested 1000 VDC and 2M Ohms. Test 2 use a Hipot and pump 1220 VAC into each wire separately testing it against all others.

this leaves me with many questions, what is IEC 60077-1 ?? is it telling me the dwell time? telling me how much leakage I can have before its a fail? Can I use a Hipot tester rated for a max of 1000 VAC for a longer dwell to still meet the customers request? since I am doing the Meg test can I bypass the hipot?

this is a new test for me to undertake so I am sorry for asking stupid questions.

Salesmen have been telling me that I need to spend $22,000 on a Cirris tester but another guy is saying that I dont need that but for $7000 I can get the same testing done using his automated tester that only hits 1000 VAC. Its just confusing to me and I have to give a presentation on what we NEED to purchase in a few days. any help would be great thanks all.

 

[7anoter4]

Since railway application is a small electrical-energetic domain you may try another forum-for instance this one: “Automotive electrical & sensor engineering Forum”. I don’t know if you have to spend 22,000 $ in order to purchase the equipment but you could spend 270 $ to buy IEC 60077-1 standard and learn the issue.
IMO you don’t have to apply Hipot on installed cable if there is no damage on the cable.
You may test the cable insulation resistance-as for instance IEC60502-1 requires:
Ch.17.1 Insulation resistance measurement at ambient temperature
Measurement with a d.c. source of 80-500 V for 1 to 5 min. The resistance has to be equal or more then:
R=Ki*log(D/d)*10^11/l l[cm] sample length [10 m to 15 m=1000 to 1500 cm]
Ki from Table 13 Electrical type test requirements for insulating compounds-for XLPE Ki=3.67-for instance.

 

[dpmac]

You need to read the spec to understand what to do and therefore what you need to purchase. I checked and I dont have any of the LV cable IEC specs. Are you performing a Qualification test or Production test?
That may make the difference between purchasing a used 4kVAC Hipot on Ebay for $150 to test 10 samples or a $22K unit to test each of 10 million you plan on making. Best to purchase and understand the spec. first and then make a decision on which equipment to purchase.

 

[woodford]

This is a production test. However we will not be making millions of cables. but several thousand still add up to quite a bit of time and with human testing errors come into play. I have purchased the spec. Reading it and understanding it are what comes next. My questions are still not coming clearly answered in my reading.

a cable harness that is used in a train inside the walls of the train that has 24V lines and 110VAC lines still leaves questions for me.

when testing is it "industry standard" to test one wire against all others? or is it one wire against all other wires that hold that same voltage type? Like all lines caring the 110 get hipoted to xxx and ignore the 24v sections as they get tested to a different spec?

I am also reading that some cables get placed on a metal plate to simulate the "chassis" and then are tested line against line and against the plate. IE, wire 1 is the AC HI line and will be tested against wire 2 tied to chassis and then I would put place wire 1 with chassis and hipot wire 2 to insure it has good isolation.

thank you for all your help so far. The more I ask the more questions I seem to have.