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Originally Posted by copiapoa  In what combination on the chassis there will be a dangerous voltage for a life?!?!?!? |
There will be no dangerous voltage unless the unit fails and the mains voltage comes in contact with the chassis.
Based on that image, even if all the grounds are lifted, there might still be a connection elsewhere in the system installation through the pin 1 of J1 and J2. This might, or might not be enough to blow the fuse. It does not apply to any standard and is definately not safe.
Here's an little piece from the IEC norm:
http://www.virtalahde.com/iec60065_ed7.1_b.pdf Quote:
15.2 Provisions for protective earthing
ACCESSIBLE conductive parts of CLASS I apparatus, which might assume a hazardous voltage in the event of a single insulation fault in BASIC INSULATION , and the protective earthing contacts of socket-outlets shall be reliably connected to a PROTECTIVE EARTHING TERMINAL within the
apparatus.
Protective earthing circuits shall not contain switches or fuses.
Protective earthing conductors may be bare or insulated. If insulated, the insulation shall be green/yellow except in the following two cases:
a) for earthing braids, the insulation shall be either green/yellow or transparent;
b) for internal protective conductors in assemblies such as ribbon cables, busbars, flexible printed wiring, etc., any colour may be used provided that no misinterpretation of the use of the conductor is likely to arise.
Wires identified by the colour combination green/yellow shall be used only for protective
earthing connections.
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Bill Whitlock has also written an excellent paper about grounding - good tips for installation techniques, too.
http://www.jensen-transformers.com/a...%20seminar.pdf
Here's a quote from the above paper, page 6.
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Consider two devices connected by a signal cable, each device having a 3-prong ac plug. One device has a ground “lifter” on its ac plug and the other doesn’t. If a fault occurs in the “lifted” device, the fault current flows through the signal cable to get to the grounded device. It’s very likely that the cable will melt and burn!
Defeating safety grounding is both dangerous and illegal - it also makes you legally liable! |
Considering how the safety ground is treated in HCL products, they are actually illegal to be sold at least in the European Union because they do not meet the CE norm. If this is found out, I'm pretty sure HCL is supposed to take back each and every one of these devices.
What is CE Marking (CE mark)? Quote:
CE Marking on a product is a manufacturer's declaration that the product complies with the essential requirements of the relevant European health, safety and environmental protection legislation, in practice by many of the so-called Product Directives.*
*Product Directives contains the "essential requirements" and/or "performance levels" and "Harmonized Standards" to which the products must conform. Harmonized Standards are the technical specifications (European Standards or Harmonization Documents) which are established by several European standards agencies (CEN, CENELEC, etc).
CEN stands for European Committee for Standardization.
CENELEC stands for European Committee for Electrotechnical Standardization.
CE Marking on a product indicates to governmental officials that the product may be legally placed on the market in their country.
CE Marking on a product ensures the free movement of the product within the EFTA & European Union (EU) single market (total 28 countries), and
CE Marking on a product permits the withdrawal of the non-conforming products by customs and enforcement/vigilance authorities.
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If a piece of equipment fails and burns down your studio or house, your insurance might not cover it because the unit in question was faulty and illegal. I think that in these cases the manufacturer is responsible, especially when selling directly. Dunno.
Speaking of smaller damage - it's also possible that if a unit with lifted safety ground fails, it can send 230v down your signal path and take quite a few other pieces with it.
Everything is possible.
HCL, as a manufacturer, should take the units with hazarduous safety ground installations back and make them proper. It's not a big job - almost any tech could do that. All it requires is taking that switch out and taking a stiff enough cable from the IEC connector's safety ground lug to the chassis, permanently connected and secured with lockwasher nuts. All the paint on the connection area should be scraped off to ensure a proper connection.