User`s guide

Serial Power Feature
Chapter 8 Configure Power Over Serial Ports 83
Serial Power Feature
The Serial Power feature available for the PortServer TS P MEI Series
allows the Digi device to power a serial device (power out) or use a serial
device to power the Digi device (power in). The advantage of this feature is
to eliminate an external power supply.
Power out is available on all ports through Ring Indicator (RI) or Data
Terminal Ready (DTR). Power in is available only through RI and only on
port one (1). The Serial Power feature is active on a specific port when that
port is configured for RS 232 operation.
• The power out budget equals one (1) watt (the total amount of power
available). The available power can be divided in any combination
between the ports but the following rules must be observed:
• RI = 5 volts @ up to 200 mA (max)
• DTR = 9 volts @ up to 100 mA (max)
• You may use DTR or RI as the source of power (power out) on any
port but you may not use both DTR and RI on the same port.
• Pinout information:
• RI is pin 1
• DTR is pin 9
• RI signaling is lost when the pin is used for power.
Chapter 8
Configure Power Over Serial Ports