Relay outputs

Relay outputs are terminated on terminals labelled by a switch schematic sign and serve for switching two-state devices with alternating or current voltage. The COM terminal is common, serving as input for switching voltage. NO and NC terminals are used as the switching voltage output.

  • NO - in the default state (no voltage), contacts are disengaged
  • NC - in the default state (no voltage), contacts are engaged

Unipi 1.1

The state (On/Off) of each relay is indicated by a LED with a corresponding label. Overload and overvoltage protection should be provided externally by a circuit breaker (ideally one for each output). Nominal current and circuit breaker type should be selected according to the load and its characteristics concerning the maximum current on the output.

Note:
If an inductive load is connected (eg. electric motors, relay coils, contactors or even the cables in extensive electric installations), we recommend protecting the relay outputs by a corresponding external element (eg. varistor, RC circuit or a suitable diode).

If a capacitive load is connected (eg. power sources of LED lights), we recommend protecting relay contacts against inrush current by connecting a corresponding thermistor to the relay's output.

Connection

The following image depicts the connection of ohmic (resistance)load with alternating voltage and connection of a three-way valve to Unipi 1.1 relay outputs:

Technical parameters

Number and type of relays 8x Finder 36.11.9.005.4001
Designation on the board RELAYx (where x represents the relay number)
Number of terminals per relay 3
Designation of terminals Schematic, on the board
Common terminal (COM) Middle terminal
Engaged without voltage (NC) Terminal away from the RPi
Disengaged without voltage (NO) Terminal closer to the RPi
Output type Electromechanic non-shielded relay
Switching voltage 250 V~ / 30 V⎓
Max. switching current (resistive load) 10 A
Switching time 10 ms / 5 ms
Mechanical lifetime 10 000 000
Electrical lifetime 100 000
Insulation voltage 4000 V
Short circuit protection Ne
Overvoltage protection Ne
Load handling External - RC, varistor, diode, thermistor

Connection

This illustration depicts connection of ohmic (resistance) load with alternating voltage to Unipi 1.1 Lite relay output:

Technical parameters

Number and type of relays 6 × SPDT Omron G5Q-14-EU
Designation on the board RELAYx (x represents the relay number)
Number of terminals per relay 3
Terminal designation Schematic, on the board
Common terminal (COM) Middle terminal
No voltage engaged (NC) Terminal engaged according to scheme
No voltage disengaged (NO) Terminal disengaged according to scheme
Output type Electromechanic non-shielded relay
Switching voltage 250 V~ / 24 V⎓
Max. switching current for VAC (resistive load) 10 A (NO) / 3 A (NC)
Max. switching current for VDC (resistive load) 5 A (NO) / 3 A (NC)
Switching speed 10 ms / 5 ms
Mechanical lifetime 10 000 000
Electrical lifetime 100 000
Insulation voltage 4000 V
Short circuit protection No
Overvoltage protection No
Load handling External – RC, varistor, diode, thermistor