Hello, I am a beginner here and need help/advice so that my nc252mp amp is safe to use. I have installed the ncore module in an abs plastic case and followed the instructions from several sites on how to hook up the iec mains, speaker terminals and xlr connectors. With a plastic case is the power earth cable connected to chassis with a screw doing its job? Is this safe? Any replies would be greatly appreciated.
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All metallic parts that you can touch without opening the enclosure should be connected to the protective earth.
From the Hypex datasheet, the amp is a Safety Class 2 device.
Rod Elliott, as usual, explains things.
Electrical Safety Requirements
Read, digest and ask if you need further guidance.
Rod Elliott, as usual, explains things.
Electrical Safety Requirements
Read, digest and ask if you need further guidance.
No, of course not.
In this case you need to *solidly* connect protective ground to power supply ground.
The cable is securely fastened to the case. Other people have replied in another thread that it does not matter, because the case is plastic and not conductive.
I read it and not sure what you are trying to tell me. The hypex amp is installed in a plastic case using a three prong iec ac socket and the internal wires supplied with the module are connected to the socket: live wire from amp to live connection on socket. Neutral to neutral. Earth ground from socket to plastic chassis via a circle clamp and screwd tightly to the chassis. The amp is connected to a preamp with balanced to unbalanced cables. Can you help me with what you are referri g to in the write up?
The Hypex amplifier only needs live and neutral supply.
It does not need safety earth so long as your implementation complies with class 2 requirements.
However, in the Rod Elliott article I linked to, section 9.1 - DIY Class II outlines the difficulties in implementing a class 2 design.
It is far simpler for the hobbyist to use an earthed metal case.
Note the safety earth wire must be connected to the case by a screw that is used for no other purpose.
It does not need safety earth so long as your implementation complies with class 2 requirements.
However, in the Rod Elliott article I linked to, section 9.1 - DIY Class II outlines the difficulties in implementing a class 2 design.
It is far simpler for the hobbyist to use an earthed metal case.
Note the safety earth wire must be connected to the case by a screw that is used for no other purpose.
That is the question I was hoping to have answered. The plastic case can not conduct and therefor safe for the hypex amp. I talked to an electrician here in Germany today and he does not see a problem even when it is connected to a preamp that has a metal case. He does not know the ends and out of the hypex amp, but only speaking from the stand point of a plastic case he said the earth wire is not needed. I will leave it connected to the case and is sepatate from everything else. What do you think?
Are there metal screws going from the outside of the plastic case to the inside?
Then it is not fully insulated.
Then it is not fully insulated.
From my point of view the hypex complies with classII.
Thus its secondary circuit - including the metal front plate - are SELV circuits.
Save without protective earth.
The plastic case is considered isolating.
For commercial use - not applicable here - this enclosure must meet fire hazard protection as well.
The only thing that may happen is the internal mains wiring coming into contact with the secondary circuitry - provisions like secure cable fixing should do the trick.
Thus its secondary circuit - including the metal front plate - are SELV circuits.
Save without protective earth.
The plastic case is considered isolating.
For commercial use - not applicable here - this enclosure must meet fire hazard protection as well.
The only thing that may happen is the internal mains wiring coming into contact with the secondary circuitry - provisions like secure cable fixing should do the trick.
Ok. The cables are securely fixed to the iec ac socket. I am not sure if we are allowed to paste links. If not, please remove. Here is a link to the case I am using.
Motec | Instrument Enclosures | OKW
I have ditched the metal fronts and back and I am using 3mm mdf.
"Solidly" = "securely".
Protective grounds need to be securely connected so there is no chance that they will accidentally become un-connected and therefore make the device potentially dangerous.