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en:hw:03-unipi11:description-of-io:03-description-of-ro [2021/05/03 11:28] avsetula |
en:hw:03-unipi11:description-of-io:03-description-of-ro [2022/07/13 08:17] lpolcerova [Relay outputs] |
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| 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. | 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 | + | * **NO** - in the default state (no voltage), contacts are **open** |
| - | * NC - in the default state (no voltage), contacts are engaged | + | * **NC** - in the default state (no voltage), contacts are **closed** |
| </WRAP> | </WRAP> | ||
| <WRAP half column 15%> | <WRAP half column 15%> | ||
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| 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. | 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. | ||
| - | <WRAP center round info 95%> | + | <WRAP center round important 95%> |
| + | **Warning:** \\ | ||
| + | If an inductive load is connected (e.g., electric motors, relay coils, contactors, or even the cables in extensive electric installations), it is necessary to protect the relay outputs with a corresponding external element (e.g., varistor, RC circuit or a suitable diode). | ||
| - | **Note:** \\ | + | If a capacitive load is connected (e.g., power sources of LED lights), it is necessary to protect the relay contacts against inrush current by connecting a corresponding thermistor to the relay's output. |
| - | 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. | + | |
| </WRAP> | </WRAP> | ||
