Differences

This shows you the differences between two versions of the page.

--- sip_relay_version [2016/04/21 08:05] – 75.177.137.2
+++ sip_relay_version [2016/04/21 08:16] (current) – 75.177.137.2
@@ Line 23: / Line 23: @@
 **Wiring**\\
+{{:relay_board3_pi.png?400|}}\\
-{{:relay_board3_pi.png|}}\\
 |Relay | P1|
 |1 | 11|
@@ Line 39: / Line 37: @@
 |11 | 24|
 |12 | 26|
+**Power**\\
+The maximum permitted current draw from the Raspberry Pi 5 Volt pins is the USB input current minus any current draw from the rest of the board and connected USB devices. For example, a typical USB power supply is 1 Amp - 0.7 Amps for the Raspberry Pi = 0.3 Amps for the 5 Volt output. If the maximum permitted current is exceeded it will cause the Raspberry Pi to shutdown. Any USB devices plugged into the Raspberry Pi will take away from the maximum permitted current (for example, a USB WiFi device uses around 0.15 Amps, leaving 0.15 Amps for the relay board). For most relay boards, each relay draws 0.07 Amps when switched on.\\
+The plugin provides some protection by reducing the number of relay channels when Active is changed (see Plugin Settings above). Before connecting any relay boards, set the plugin to 1 Relay channel to be sure at most only 1 relay will turn on while you get things setup. Be sure the plugin is enabled, if it is not enabled the OSPi program will default to OpenSprinkler board mode which will cause 3 relays to be activated if a relay board is connected.\\
+OSPi defaults to sequential mode which means only one station (relay) is on at a time. If sequential mode is disabled (in OSPi: Options, Station Handling), you must be very careful not to exceed the maximum permitted current. If you need to have more than one relay on at a time, you could use a USB power supply capable of higher current output, or use a separate 5 Volt power supply that only powers the relay board(s).\\
+{{:sprinkler_relay_wiring.png?400|}}\\