Relay outputs

Relay outputs in Robopipe controllers are used for switching two-state devices and support both AC and DC voltages. Connections are made through ROx or ROy.x terminals alongside a shared COM terminal. The COM terminal enables the switching of voltage to the respective relay output. Relays are normally open (NO) by default, meaning there is no connection between the COM and RO terminals unless the relay is activated.

Each relay’s status (On/Off) is displayed via a corresponding LED indicator. Protection against overloads and overvoltage should be implemented externally, typically with a dedicated circuit breaker for each output. The breaker specifications should align with the load's characteristics.

Protection Measures

• Inductive Loads (e.g., motors, relay coils, contactors): Protect the relay using a suitable external component like a varistor, RC circuit, or diode to prevent voltage spikes.

• Capacitive Loads (e.g., LED power supplies): Use an appropriate thermistor at the relay's output to handle inrush currents and safeguard relay contacts.

Connection

• Connect the COM terminal to the voltage source or desired power connection

• Attach the load to the corresponding RO terminal

• For inductive or capacitive loads, ensure additional external protection (e.g., varistor or thermistor)

Special Functions

DirectSwitch

• DirectSwitch links digital inputs to relay or digital outputs, enabling rapid response independent of control software.

• Modes:

  • Copy - Output replicates the input state

  • Inverse Copy - Output state is the logical negation of the input state

  • Switch - Toggles the output state on the input’s rising edge

  • Block - Deactivates DirectSwitch

Key Notes:

• DirectSwitch requires matching input and output labels (e.g., DIy.x and ROy.x)

• DirectSwitch cannot simultaneously control multiple outputs or mismatched labels

• When DirectSwitch is active, manual output control is disabled unless the ForceOutput register is temporarily set to TRUE

Default Configuration

Relay outputs revert to stored settings after a reboot or power cycle.

Parameter	Default Setting
Output Value	FALSE

Master Watchdog

The Master Watchdog monitors software activity and automatically reverts relay outputs to safe defaults if no commands are detected within a set timeout period. This mechanism prevents damage or hazards caused by communication failures, hardware issues, or software errors.

Technical Specifications

Parameter	Specification
Output Type	Electromechanical, non-shielded
Output Terminal	RO
Common Terminal	COM
Contact Type	Normally Open (SPST-NO)
Relay Model	FTR-F3AA024E-HA
Max Switching Voltage	250 V AC / 30 V DC
Max Switching Current	5 A
Max Common Terminal Current	10 A
Short-Term Current Overload	5 A
Mechanical Lifespan	5,000,000 cycles
Electrical Lifespan	Up to 100,000 cycles
Operate/Release Time	10 ms
Designed Load Type	Resistive
External Protection Required	RC circuit, varistor, diode, thermistor
Short Circuit Protection	No
Overvoltage Protection	No
Galvanic Isolation	Yes
Insulation Voltage	4,000 V