Electromagnetic Radiation levels 4

[EEJaime]

Has anyone out there run across any studies or guidelines as to what level of emi produced by electrical switchgear, transformers, etc..., is sufficient to adversely impact electronic equipment such as computers, servers, etc...? We have a situation where the owner has installed computer work stations on the opposite side of a wall to an electrical room housing among other things a battery inverter unit which is immediately opposite a CRT which is experiencing screen glitches such as horizontal lines continuously running up the screen. We have gotten readings of from 10 to 240 milligauss at the affected unit. Anyone have experience in this type of application?

 

[alehman]

This is a common problem. CRT displays are very sensitive to magnetic fields - as little as 10mG can be a problem. The easiest solutions are usually to move the monitors or use LCD displays. If those are not an option, sometimes magnetic shielding can help.

http://amuneal.com/pages/magapp-comp.php#

http://www.mushield.com/

http://www.lessemf.com/computer.html

http://www.magnetic-shield.com/histories/22804.html

 

[chicopee]

make sure your shield is effective for the range of wavelengths of the EMF.

 

[wareagle]

I have seen copiers and microwaves cause similar problems because of their proximity to the CRT or were on the same circuit as the CRT. One thing you can try is to temporarily connect an extension cord from the other side of the room an use it to power the CRT. If it helps then you need a new circuit.