VFD for old Myford ML8 wood lathe (0.5HP, single phase)

[happysteve]

With drives there is a requirement for isolation normally by use of a contactor that will automatically drop out if say an E-stop is hit (situation dependent) or more so a power failure due to the charged electronics within the drive which can take several minutes to discharge, all someone has to do here is leave that DP switch down and unplug it exposing the plug pins still in line with a charged Drive.

Ah, right, see what you mean. Thanks.

I can spot so many other breaches but its that one that stands out, the screening issue can see RF-interference locally and also harmonic issues in the mains.... I'm going to ask although your call if you want to divulge but how much did you pay for this?

£400+VAT.

 

[Darkwood]

From the manual just to give you an idea of the breaches that may have been done here, I lack some info but some of it is obvious to me :shocked3:-

The CFW-10 inverter series was designed considering all safety andEMC (ElectroMagnetic Compatibility) aspects.The CFW-10 units do not have an intrinsic function until connected with other components (e. g. a motor). Therefore, the basic product isnot CE marked for compliance with the EMC Directive. The end usertakes personal responsibility for the EMC compliance of the whole installation. However, when installed according to the recommendations described in the product manual and including the recommended filters and EMC measures the CFW-10 fulfill all requirements of the (EMC Directive 89/336/EEC) as defined by theEN61800-3 "EMC Product Standard for Adjustable SpeedElectrical Power Drive Systems - specific standard for variable speed drives.The conformity of the complete CFW-10 series is based on tests performed on sample models. A Technical Construction File (TCF)was prepared, checked and approved by a Competent Body.

The following items are required in order to have an appropriated installation:
1) The motor cable shall be armored, or installed inside a metallicconduit or trunking with equivalent attenuation. Ground the screen/metallic conduit at both ends (inverter and motor). (poor wording here screened should be key word)
2) Control (I/O) and signal wiring shall be shielded or installed insidea metallic conduit ortrunking with equivalent attenuation.as possible.
3) The inverter and the external filter shall be closely mounted on acommon metallic back plate. Ensure a good electrical connectionbetween the inverter heatsink, the filter frame and the back plate.
4) The wiring between the filter and the inverter shall be kept as short.
5) The cable shield (motor and control) shall be solidly connected tothe common back plate, using metallic brackets.
6) Grounding shall be performed as recommended in this user’s guide.
7) Use short and thick cables to ground the external filter or inverter.When an external filter is used, ground only the filter (input) - theinverter ground connection is performed through the metallic backplate.
8) Ground the back plate using a braid, as short as possible. Flatconductors (e.g. braids or brackets) have lower impedance at highfrequencies.
9) Use cable glands whenever possible.