Terminal Block Basics

We have all seen this type of wire connection: exposed twisted wires
- Does it work? Yes.
- It allows electricity to flow
- It is NOT safe. It’s messy and unreliable.

An improvement on that connection would be a wire nut and wires.
We are all familiar with wire nuts. They are very commonly used to make electrical connections.

- They provide much more safety
- They are more secure.
- Not terribly organized, but get they job done.

An even better solution would be a terminal block. It functions no differently that the two examples I just showed you, except that:
- Commonly used in industrial and commercial applications
- It is much safer
- More secure
- Allows for more connections options
- And gives us the ability to keep our wire much more organized.

Types of Terminal Blocks

They are several different types of terminal blocks that can be used to accommodate different situations, uses and applications

Single Level Pass through terminal block
Just like the wire nut, this type of terminal block is simply used to connect two wires together with a common junction point. This is helpful when a component needs to be disconnected or we simply want to isolate something within the circuit. These are the most common types of terminal blocks you will see in industrial applications.

Ground Terminal Blocks
Look and function and function almost exactly like most pass through terminal block with one exception. They are grounded.
These blocks and a metal connection from where the wire is terminated all the way to the bottom of the block where it will clamp into the panel.

This allows us to ground an electrical circuit without have to run a wire to the main ground connection on a breaker or surge protector

These functions in a very similar manner to the basic pass through terminal block with one exception. There is a fuse located in the terminal block.

This fuse allows us to protect items that we are wiring so that they do not encounter to much voltage or current.

Multilevel terminal blocks
Just like with a basic pass through terminal block, the multilevel terminal block allows for an electrical connection, or junction point. The advantage to using a multilevel terminal block is that it can make 2 or 2 electrical connections in the same block.

Also, this block can incorporate fuses, and have the ability to be ground.

So, in some cases these blocks can be a combination of all the other blocks we have talked about.

Disconnect Terminal Blocks
Similar to a fused block, the disconnect allows us to stop the flow of electricity by lifting this lever on the terminal block. Unlike fuse blocks, the are a more permanent solution, but will not provide any protection in the event of a power surge.

By doing this the metal will no longer be in contact and no electricity will flow.

Safety is one of the main reasons terminal blocks are used. The connections points are very secure, and the design does not allow for short circuits or shock hazards to be a common occurrence.
They are very durable. This is why they are the preferred connection method for industrial use. They can stand up to harsh environments.

They give us the ability to isolate components, sensitive instrumentation, power, etc.

Additional Links -

Website:
Engineering Page:
Panel Fabrication Page:
Procurement Services Page:
Manufacturers Page:
Terminal Blocks & Connectors:
Panel Hardware:
Enclosure Accessories:
PLCs & IO:
Wiring Duct:

[jamesalves]

Great video...exactly what I had been looking for, thanks for producing.

[JerrodLandon]

It would be nice to see it closer up or some highlight lines to show what he is talking about like on the ground block

[JenniferSteeves]

Thanks for doing this video!!! Started a new job making cable, wiring and assembling cabinets and mounting terminal blocks .

[TaiBreland]

This is a great explanation!!! Thank you for your time!!!

[sagarverma]

Thank you for the initiative of sharing information!!
That was very informative and to the point.

[JenniferSteeves]

Very helpful video when you didn’t know wtf a terminal block is !

[sallynall]

This was helpful for teaching GCSE physics-thank you so much!

[TomTon-yb]

I’m working at maverick power I learn a lot and understand more in this Video thanks

[methuselahbwalya]

Thanks Josh. I love all your videos, they helpful

[qhazwel]

Hey Josh, I am trying to make a DIY fuel injector cleaning system. I have this device I bought on eBay to clean one connector at a time. Which type of a terminal block would I use to connect this cleaning device to 4 injectors at the same time? Thanks in advance! It will involve a positive and negative set up.

[marvinhensbergen]

What I don't see in this video.. My main question.. How combine terminal blocks.. I see jumpers or screw connectors on top, but in allot of webshops, I don't see the hardware needed to connect them together, for example for a power bus.

[MINHAJUDDINKhan]

nice. add use of lugs used in wire termination.

[lindalyn]

Good educational thank you for quick and free lesson 👍

[ramjanansari]

tarminal block kitne tarah ke hote hai

[TheMudfly]

Thank you time to play with the wiring in my house yeee-hawww

[abilyn-siyo]

if you answer me this i will subscribe i swear, if im requested a terminal block that's 22-10 awg, but 10 amp and i can offer one similar but 30 amp, is that a bad or a good match and why ? you will make my day if you answer this to me

[MrFernandoBedoya]

No info regarding purchasing a terminal block.
What is PT 1.5, PT 2.5, ...

[petemclinc]

1:39 WTF, power coming in and leaving from the same side?

[MINHAJUDDINKhan]

missed the disconnect terminal blocks. aka knife edge.. tbs

[narjisphoto]

u didnt mention how to wire a pa4730 terminal block