Difference between revisions of "Relay"
(→Pinout) |
|||
Line 94: | Line 94: | ||
This is a demo to send things using SPI to the lcd board. The SPI routines there are applicable for the dio and relay boards as well. |
This is a demo to send things using SPI to the lcd board. The SPI routines there are applicable for the dio and relay boards as well. |
||
== |
== additional considerations == |
||
Each relay draws about 70mA. This means that if you have the bigrelay board, and turn on all six relays, the current draw will amount to about 400mA. If you have the board connected to a raspberry pi, this might stress your polyfuse on the 5V line, and/or exceed the capabilities of your powersupply. You can supply extra 5V power on the 5V lines of other connectors on the board. For example, if you have the SPI version, you can mount one of the I2C connectors and provide GND and 5V on pin 1 and 4 respectively. |
|||
Note that your extra powersupply is likely to start powering the raspberry pi a bit as well. (Due to the voltage drop over the polyfuse in the raspberry pi, the 5V on the relay board is likely to be a bit higher than that what ends up on the 'pi itself.) You could consider powering the whole system through this extra powersupply, but be careful, the polyfuse on the pi is now circumvented. |
|||
== Default operation == |
== Default operation == |
Revision as of 13:46, 10 December 2012
This is the documentation page for the SPI_relay and I2C_relay boards.
Overview
This board enables you to drive two relays.
Assembly instructions
None: the board comes fully assembled.
External resources
Datasheets
Additional software
Related projects
Pinout
For the SPI connector see: SPI_connector_pinout.
For the I2C connector see: I2C_connector_pinout.
pin | function | remark |
---|---|---|
1 | NO 1 | Normally open contact for relay 1 |
2 | C 1 | center connection for relay 1 |
3 | NC 1 | normally closed contact for relay 1 |
4 | NO 2 | Normally open contact for relay 2 |
5 | C 2 | center connection for relay 2 |
6 | NC 2 | normally closed contact for relay 2 |
Only for BigRelay: | ||
7 | NO | Normally open contact for relay 3 |
8 | C | center connection for relay 3 |
9 | NC | normally closed contact for relay 3 |
10 | NO | Normally open contact for relay 4 |
11 | C | center connection for relay 4 |
12 | NC | normally closed contact for relay 4 |
13 | NO | Normally open contact for relay 5 |
14 | C | center connection for relay 5 |
15 | NC | normally closed contact for relay 5 |
16 | NO | Normally open contact for relay 6 |
17 | C | center connection for relay 6 |
18 | NC | normally closed contact for relay 6 |
LEDs
There is one power led.
On the regular relay board are two LEDs near each of the relays indicating the state of the relays. The BigRelay board doesn't have indication LEDs.
Jumper settings
Protocol
To make the relay PCB do things, you need to send things over the SPI bus to the PCB.
The general overview of the protocol is here.
The specific commands for the relay PCB are explained on the page about the spi_dio board, as the two boards share the same protocol: spi_dio_protocol .
For arduino, a sample PDE is available, called ardemo_lcd.pde, also at BitWizard software download directory .
This is a demo to send things using SPI to the lcd board. The SPI routines there are applicable for the dio and relay boards as well.
additional considerations
Each relay draws about 70mA. This means that if you have the bigrelay board, and turn on all six relays, the current draw will amount to about 400mA. If you have the board connected to a raspberry pi, this might stress your polyfuse on the 5V line, and/or exceed the capabilities of your powersupply. You can supply extra 5V power on the 5V lines of other connectors on the board. For example, if you have the SPI version, you can mount one of the I2C connectors and provide GND and 5V on pin 1 and 4 respectively.
Note that your extra powersupply is likely to start powering the raspberry pi a bit as well. (Due to the voltage drop over the polyfuse in the raspberry pi, the 5V on the relay board is likely to be a bit higher than that what ends up on the 'pi itself.) You could consider powering the whole system through this extra powersupply, but be careful, the polyfuse on the pi is now circumvented.
Default operation
Future hardware enhancements
Future software enhancements
Changelog
1.0
- Initial public release