Modushop Enclosure Screening

[ruffrecords]

Just a heads up. I have a hum problem with a current project that uses a modushop case. This type has aluminium front and rear panels held together by side extrusions. Top and bottom covers are steel and held in place by pairs of nuts/bolts that run in a slot in the side extrusions

There is near perfect continuity between the front and rear panels via the side extrusions. However, there is over 40 ohms between the (bare metal of the) top and bottom panels and the front/rear panels. I am fairly certain this is due to the method of mechanical fixing of the top and bottom panels which does not make a good electrical connection. The result is the top and bottom panels do not act as screens. So I shall be making a direct connection.

Cheers

ian

 

[johnheath]

Just a heads up. I have a hum problem with a current project that uses a modushop case. This type has aluminium front and rear panels held together by side extrusions. Top and bottom covers are steel and held in place by pairs of nuts/bolts that run in a slot in the side extrusions

There is near perfect continuity between the front and rear panels via the side extrusions. However, there is over 40 ohms between the (bare metal of the) top and bottom panels and the front/rear panels. I am fairly certain this is due to the method of mechanical fixing of the top and bottom panels which does not make a good electrical connection. The result is the top and bottom panels do not act as screens. So I shall be making a direct connection.

Cheers

ian

I use these enclosures a lot and have found the contact between the parts is not always very good. I always use a piece of wire to improve the contact especially between the top lid and the backpanel. I use 5mm clips so I can remove the lid completely before service or other.

Best regards

/John

 

[warpie]

Maybe removing the paint with sandpaper would help ?

 

[ruffrecords]

I use these enclosures a lot and have found the contact between the parts is not always very good. I always use a piece of wire to improve the contact especially between the top lid and the backpanel. I use 5mm clips so I can remove the lid completely before service or other.

Best regards

/John

Thanks John. Good to know I am not the only one.

Cheers

ian

 

[Kingston]

I have used modushop cases exclusively for the last decade. Indeed the painted steel and heatsink shaped etc. aluminum extrusions do not make good contact. I always dremel away the paint/anodization with some gentle dremel tip at the sites of contact. 5 mm around the screw holes basically. Perfect Faraday cage 0 ohm around the case doing this.

Now if I could stop some of the steel parts rusting. Not a big deal but unsightly taking off the lids for service.

 

[ruffrecords]

I have used modushop cases exclusively for the last decade. Indeed the painted steel and heatsink shaped etc. aluminum extrusions do not make good contact. I always dremel away the paint/anodization with some gentle dremel tip at the sites of contact. 5 mm around the screw holes basically. Perfect Faraday cage 0 ohm around the case doing this.

Now if I could stop some of the steel parts rusting. Not a big deal but unsightly taking off the lids for service.

Thanks for the tip. I'll see if I can do that without it becoming unsightly!!

Cheers

Ian