1756-TBCH wiring arm assembly

[@Yoyosten99]

What are the white/greenish trays that come with these terminal blocks? Looks like 8 tabs and 8 hooks/clips. Can't for the life of me figure out what they're for. Never seen any of our other slots use them.

[@abplctestbench759]

Hi: Another bad idea from AB. These are supposed to be like the old style Keying bands that used to come with PLC5 chassis. They were responsible for a lot of damage to chassis and modules. You can set them up in a configuration of your choice to make sure the correct module is inserted into the correct wiring arm. A nice idea, but no idea if anyone uses them and AB does not give any guidance about using them. Recycle bin is best location IMO.

[@brandonly27]

Do the TBCH modules come with the 1756 IO modules when you order them?

[@abplctestbench759]

HI Brandon: No they do not. You have to purchase. They have blanks as you see me wiring in the video. They also have pre-made using the 1492 system. Screw terminals or spring pressure. Thanks for commenting.

[@brandonly27]

@AB PLC Test Bench okay. I just got an email from a distributor, too. The Email read "if we included the terminal blocks with the the IO cards, half of them would be thrown away". He then sent me a list of terminal blocks to choose from. Thanks for your response. Perhaps you could also do a video on differential wiring vs. single ended wiring with some examples.