contact resistance
contact resistance
(OP)
Hi,
I have installed some electrical equipments in a vehicle and i have to measure the contact resistance for every grounding (equipment to chassis) that i've made.
My question is: Do you know what is the electrical standard (MIL) that specifies what is the right value for the contact resistance?
Thank you!
Martin
I have installed some electrical equipments in a vehicle and i have to measure the contact resistance for every grounding (equipment to chassis) that i've made.
My question is: Do you know what is the electrical standard (MIL) that specifies what is the right value for the contact resistance?
Thank you!
Martin





RE: contact resistance
You're best bet is to go back and check the formal requirements for your project.
The lowest standard that I recall seeing is 2.5 milliohms.
RE: contact resistance
My problem is that the customer doesn't have any kind of formal requirements for this issue.
I found in MIL-STD-202G Method 307 the right procedure, but i didn't manage to find the maximmum value for it.
The measurements i've done were lower than 2.5 mO - so that's a relief.
Martin
RE: contact resistance
RE: contact resistance
RE: contact resistance
http://www.dstan.mod.uk/data/58/006/00000100.pdf
This tends to ask for bonding resistances not to exceed 2 milliohms.
DEF STAN 59-41 Pt 6 offers useful guidance on why this sort of bonding is important, and how it might be achieved.
http://www.dstan.mod.uk/data/59/041/06000100.pdf
A.
RE: contact resistance
I manage to find the proper standard for grounding, bounding and shielding: MIL-STD-1857 (HDBK from 1998).
The contact resistance is 2.5 milliohms.
Thank You!
RE: contact resistance
Similar idea to yours - use a current transformer and energise the primary from a variac. Obviously it helps to have some idea of the kneepoint voltage - a Class X CT from a high-Z relay scheme is ideal for making a controllable high (kA-level) current source.
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