A maximum of seven units of EX modules can be attached to HTB. In addition to expansion of I/O for standard input and output, analog I/O can be used.
You can use the following EX module models and features.
EX Modules: Models and Features
| Feature | Type | Description | Browse to | 
| Standard Input | EXM-DDI8DT | DIO Module: 8-input sink/source | |
| EXM-DDI16DT | DIO Module: 16-input sink/source | ||
| Standard Output | EXM-DDO8UT | DIO module: 8-output sink | 
 | 
| EXM-DDO8TT | DIO module: 8-output source | ||
| EXM-DRA8RT | DIO module: 8-output relay | ||
| EXM-DDO16UK | DIO module: 16-output sink | 
 | |
| EXM-DDO16TK | DIO module: 16-output source | ||
| EXM-DRA16RT | DIO module: 16-output relay | ||
| Standard I/O | EXM-DMM8DRT | DIO Module: 4-input sink/source DIO module: 4-output relay | |
| EXM-DMM24DRF | DIO Module: 16-input sink/source DIO module: 8-output relay | 
 | |
| Analog Input | EXM-AMI2HT | Analog Module: 2-input | |
| EXM-AMI4LT | Analog Module: 4-input | 
 | |
| EXM-ARI8LT | Analog Module: 8-input | 
 | |
| Analog Output | EXM-AMO1HT | Analog Module: 1-output | |
| EXM-AVO2HT | Analog Module: 2-output | 
 | |
| Analog IO | EXM-AMM3HT | Analog Module: 2-input Analog Module: 1-output | |
| EXM-AMM6HT | Analog Module: 4-input Analog Module: 2-output | 
 | |
| EXM-ALM3LT | Analog Module: 2-input Analog Module: 1-output | 

While HTB is powered ON, such as when it's running, do not install or remove HTB or the EX module.