maximum weight for stuff hanging off connectors?

[SArepairman]

So sometimes we see modules that hang off of equipment attached by BNC/banana connectors,  what is the maximum safe weight to hang something?

When I made several altoids tin plug in modules I designed them specific to my equipment and supplied cribbing inside of the container (some coins or whatever), so it fit well and put no strain on the equipment.. if you set up the cribbing correctly.

But what if I wanted to sell something that plugs directly into a oscope or multimeter? Could I possibly be selling something that damages someones equipment? I know there are radically different setups and I can't expect someone to make cribbing that support the module plugged into their multimeter 3 feet off the bench(I could see someone cutting dowels or stacking the old school text books....) but its pretty ridiculous if its more then a few inches, no one wants to ghetto up their work bench with scaffolding.

Now, I see sheilded banana plugs (like multimeter probes) being pretty robust. But what about a BNC connector on an oscilloscope, N on a spectrum analyzer....

[kizzap]

So many variables you will need to take into account. From the top of my head:

Flex in the PCB,
possible breakage in the PCB,
the glue holding copper to the fibreglass shearing,
the solder joints shearing,
warping the plastic housing,
whether the BNC is bolted to the housing or not,
the material the BNC connector is made of,
the wall thickness or the BNC connector.

That said, I would think they would be able to hold a small amount of weight, but if you have something heavy, I would suggest connecting it with coax, and not leave it hanging.

[SArepairman]

So many variables you will need to take into account. From the top of my head:

Flex in the PCB,
possible breakage in the PCB,
the glue holding copper to the fibreglass shearing,
the solder joints shearing,
warping the plastic housing,
whether the BNC is bolted to the housing or not,
the material the BNC connector is made of,
the wall thickness or the BNC connector.

That said, I would think they would be able to hold a small amount of weight, but if you have something heavy, I would suggest connecting it with coax, and not leave it hanging.

ah well how many AA batteries are a small amount of weight?

[amyk]

It's not really weight but torque - a long protruding module would be far worse than a stubby one, even if it weighed less.

[SArepairman]

It's not really weight but torque - a long protruding module would be far worse than a stubby one, even if it weighed less.

excellent point