True.
In fact I have seen low voltage switchboards which do not even have incoming circuit breakers.There is a direct connection of transfromer low voltage side to the switchgear busbars through a bus duct. Maybe if it is through a cable we might need to consider cable protection. Any further...
We have been using WEG motors for some of our projects and haven't recieved any failure reports as yet. To avoid failures in high voltage motors it is prudent to have stringent testing criteria in your specification/contract for instance to have turn to turn insulation testing on stator coils...
Thanks, thanks to all..
PWR-It is a relief to know that this technology is being used somewhere in this world.With such an experience I would certainly like to consult you before pushing this application in my projects. Could you send me your email address at pandeys@mantraonline.com
Dandel-...
Please check the application of the panelboard. While going through a Siemens online training on Panelboards I found a following caution.
" For a panelboard to be considered for lighting and appliance branch circuit more than 10% of the overcurrent devices must be rated for 30A or less"
Any...
Thanks Pals
Should have used keyword search. It is available in :
http://www.eng-tips.com/viewthread.cfm?SQID=21916&SPID=238&newpid=238&page=3
Now I want to know if anybody has used series rating/ Cascading applications with selective discrimination in any of your industry. I have read some...
Or have you seen a power distribution circuit where the upstream circuit breaker is from a MCC/PMCC and feeds another distribution board which has outgoing breakers having lower short circuit ratings. There is again no fuse used anywhere in the circuit.
I would like to know if anybody has used circuit breakers in a power distribution circuit where the upstream circuit breaker and the downstream circuit breaker ( maybe incomer to another distribution board) have different short circuit ratings. There is no fuse used anywhere in the circuit.
In short , the IT System is such that the neutral is unearthed. All exposed-conductive-parts of the installation are connected to independent grounding electrodes. When there is a great need of continuance and maintainence of service this type of a earthing system is chosen.Since when the first...
I think I get your question. In European systems the grounding systems are classified as TT, IT and TN systems.
In accordance with IEC 364-4-41 a low voltage distribution system is usually characterized from electricity source to terminal equipment with the following:
i)grounded power supply...
In short the above implies that the motor and the branch circuits need not be oversized for full load when only an intermittant operation of the machine is required in a process.
Hi
I think NEC has this table to match the Concept of IEC. IEC and European standards allow motors to have a rating for short time/Intermittant duty such as S2, S3 etc.It is followed by the indication of the duration of the duty. These ratings are mentioned on the nameplate of the motor if it...
For schuko sockets you can refer to the website:
http://www.mennekes.de/content/folder/1081792/1
and the following contact details in GERMANY:
Mennekes Elektrotechnik GmbH & Co. KG
Area Sales Manager
*Phone +49 2723 41-234
*Fax +49 2723 41-333
The short circuit withstand levels are very important in cases where manufacturer's provide motor terminal boxes which are fabricated instead of being cast , due to its large size to accomodate larger sizes of cables.
Also some of the manufacturers confirm the that the box can withstand fault...
Hi
Since you have already purchased the motor , it would not matter if you run it continuously within the service factor value , and within temperature limits of class F insulation since the motor with the specified service factor is designed to be operated continuosly at that value.
If it...
