Many Automation vendors sell you products which are nothing but bait-and-hook. One of the best example is Click PLC advertised by AutomationDirect to be a $100 PLC but by the time you configure a system and add external components to make it in to a acceptable PLC system, cost becomes more than $800.

Here's an example

AutomationDirect wants you to believe that you can get a Click PLC for $100. It is a classic “bait-and-hook”.

Here is the truth: For a simple 16 DI, 8DO 4RLO system

• You need a Power supply module: $59
• CPU with 8DCI, 6 DCO: $104
• 8 Input DC module to get up to 16 Inputs: $53
• 8 Outputs, 100 ma, module: $57
• 4 Relay output module: $68

So far we are at $341

We need ZIP links to be able to connect wires to IO terminals. Each ZIP link along with the cable costs about $70, 4 ZIP links in this system will add: $279
Now we are at $620
For relay contacts you need snubbers to supress transients caused by inductive loads (* Full explanation in Note 1 below). So, for just 4 contacts: (27+5)x4=$128
Now we are at $748

DC solenoids have an inrush current 3-4 times its steady state current, requiring external relays and fuses

• Need 2 Amps Solid State Relays to drive just 2 DC solenoids: (57+5)x2=$124
• Need Fast acting fuses to protect DC outputs driving solenoids, not short circuit proof but better: (8+5)x2=$26
• Additional components to make a system somewhat reliable: $278

Total: $898, and not $100.

EZAutomation on the other hand gives you products that are all inclusive and do not need external components with additonal material cost and additional labor cost to design a reliable automation system. It's PLC DC outputs are short circuit proof. It's relay contacts have built-in snubbers. No external battery modules are ever needed. No CPU or memory modules are needed. It's all inclusive.