RMC75 Motion Controller Expansion Modules

D8 - Eight Software-Configurable Discrete I/O

The D8 adds eight discrete inputs or outputs to the RMC70 Series motion controller. Up to 32 I/O may be added if all four Expansion modules are D8s.

Each I/O can be individually configured in software as an input or output. Inputs and outputs are polarity independent. However, since there is just one input common and one output common, all inputs must be the same polarity, and all outputs must be the same polarity, but inputs need not be the same polarity as outputs. That is, outputs can switch high side or low side, and the inputs can be operated with either polarity signals.

Inputs and outputs are 12-24VDC rated and optically isolated from the controller. Since all inputs share a common connection, there is no isolation between input points. Likewise, all outputs share a common pin and therefore do not have isolation between outputs.

The D8 can be used for the following purposes:

• Control discrete outputs from User Programs
• Control User Program flow based on discrete I/O state
• Start User Program tasks based on discrete inputs

AP2 - Analog Inputs for Position-Pressure and Position-Force Control

The AP2 module adds two analog inputs for pressure or force (single-input or dual-input differential) feedback, and is required for dual-loop position-pressure or position-force control. The AP2 interfaces to transducers with the following characteristics:

• Voltage: ±10V
• Current: 4-20mA

Each 16-bit input of the AP2 can be individually configured to interface to voltage or current output transducers. The AP2 is required for dual-loop position-pressure or position-force control.

Supported Reference Types

• Position
• Velocity
• Pressure
• Force (single-input)
• Force (dual-input, differential force)

If you need analog reference inputs, but do not need position-pressure or position-force control, choose the **EXP70-A2** expansion module instead.

A2 - Two Analog Reference Inputs I/O

The A2 module adds two analog reference inputs for position, velocity, pressure or force (single-input or dual-input differential) feedback.

The A2 interfaces to transducers with the following characteristics:

• Voltage: ±10V
• Current: 4-20mA

Each 16-bit input of the A2 can be individually configured to interface to voltage or current output transducers.

The A2 generates a 10VDC exciter output, which can replace using an external precision power source in some potentiometer applications. This low noise reference also provides the accuracy benefits of ratiometric tracking.

Supported Reference Types

• Position
• Velocity
• Pressure
• Force (single-input)
• Force (dual-input, differential force)

If you need analog inputs for position-pressure or position-force control, you must use the EXP70-AP2.

Q1 - Quadrature Input

The EXP70-Q1 Expansion module adds one quadrature input for position feedback, and a high-speed input for homing or registration of the quadrature input. The RMC70 supports up to two Q1 modules. The Q1 is typically used to provide a reference position input.

Supported Encoders

The Q1 module interfaces only to quadrature encoders with Differential Line Driver (RS-422) signals. Single-ended line drivers (TTL) are not supported due to low noise immunity.

The Q1 supports the A and B quadrature signals. It does not support an index (Z) pulse.

Registration Input

The Registration input (Reg) input is a high-speed input for homing or registration of the quadrature input. The Registration input is compatible with 12-24V signals.

Selectable Termination for Daisy-Chaining

The A and B inputs have selectable termination allowing up to 32 EXP70-Q1 modules to be daisy-chained with only the last input terminated. This allows up to 64 slave axes (2 axes per RMC70) to be geared to one master quadrature signal.