I don't seem to be getting any reply for this post. Perhaps i should refine my question. Actually I'm interested to know what is the safest distance away from High Voltage panels for IR scanning without having the risk of spark over, while not compromising on the image quality? What are the common industrial practice for this? Appreciate your thoughts.
There are special observation ports that can be installed in the HV switchgear to eliminate the need of opening any doors or panels.
Basic NFPA-70E requirements imply that just opening a door for observation requires appropriate arc-flash PPE. The IR equipment manufacturers are working to come up with solutions that don't require opening of doors.
dpc, u mentioned on the observation ports. what are those? would appreciate if u could provide me with the links to find those.
actually i have another question. recently, we have a unit of ACB (Air circuit breaker) that burnt down due to loose connection at one of the terminals. this is a ABB Sace F5C slot-in type ACB. we plan to monitor all the ACBs using the IR thermography but the problem is the terminals are inaccessible. it's protected by a layer of PVC panel and to top it with the cabinet door. I'm wondering is there anyone that has successfully monitor ACB of this type? if so, how?
If the terminal is in the back then your only alternatives are remove the back panel with suitable safety review or install special observation ports.
There are two kinds of observation ports.
One is a fisheye port offered by Mikron. Relatively inexpensive per port but you have to have the Mikron camera and special attachment to use it. Look at
Another type of ports are windows selected as transparent to infrared frequencies. These are much more expensive per port but can be used with any camera. Google for Hawke windows or check snellinfrared.com message boards which have a lot of discussion (also dpc may provide some more ino.
With either option you should review for yourself whether you consider it safe.
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I don't have any actual experience with either type so nothing to add. But as I understand the info received from Mikron, this port is basically a small hole in the panel that you stick the special fish-eye lens up against. I have to wonder how safe that would be if there was actually an arcing fault while inspection was being done. Obviously, if a door does not have to be opened, or a panel removed, this will be safer than most other alternatives, but there is no assurance that the door or panel will even stay on during an arcing fault, unless it is arc-resistant gear.
Certainly not risk-free, but probably lower risk than opening the doors.