Even though the PLC and the drive are two independent systems, they must function as a complete motion control system, below are the typical adjustments:
• The position command of the Ultra 1500 accommodates open collector inputs to a maximum of 900 kHz. While the pulse train frequency output from the MicroLogix controller is limited to 20 kHz, greater frequencies can be accommodates using a third party stepper card.
• The servo drive of Allen Bradley Ultra 1500, as well as many other motion drives, requires 5V dc levels for step or direction. Recently all MicroLogix modules are powered by 24 Vdc, have 24 Vdc inputs, and have a combination 24 Vdc solid state and relay outputs.
• Ultra 1500 Step or Direction inputs are for 5V interfaces, but MicroLogix outputs are 24V. A resistor of 2.2Kohms limits current through the opto-isolated input of the Ultra 1500.
• MicroLogix inputs are wired as sourcing inputs and are active low NPN.
• The discrete inputs of Ultra 1500 are active low NPN, but are not compatible with MicroLogix FET outputs. Only MicroLogix relay outputs connect to Ultra 1500 inputs.
• To configure Ultra 1500 inputs and outputs must be using Ultraware software as below:
1. input 1 : Fault Reset
2. Input 2 : Drive Enable
3. Output 1 : Drive ready