nutdrv_siemens-sitop - Man Page

nutdrv_siemens-sitop -h

nutdrv_siemens-sitop -a UPS_NAME [OPTIONS]

nutdrv_siemens-sitop supports Siemens UPS models from the SITOP UPS500 series​. Some models have a serial port, others have a USB port​. The models with USB port actually contain a serial-over-USB chip, so as far as this driver is concerned, all models are serial models​. This driver should work with all models in the SITOP UPS500 series, as long as your kernel has support for the serial port device (see section USB driver below)​.

The UPS is configured via DIP-switches​. For correct functioning in combination with NUT, set the DIP-switches to the following:

switch 1-4

Choose whatever suits your situation​. Any combination will work with NUT​.

switch 5 (⇒ / t)

Set to OFF (t)​. This ensures that the UPS will not cut power unless NUT tells it to do so (or unless the batteries are exhausted)​.

switch 6-10 (delay)

Set to OFF (minimum delay)​. Setting a higher delay will actually also work, but any command from NUT will be delayed as well before being executed by the UPS​. With the minimum setting, it will already take 5 seconds before a command from NUT is executed​.

switch 11 (INTERR​.)

Set to ON (interrupt the output after the timer expires)​. This ensures that the UPS briefly interrupts the output power in response to the shutdown​.return command​. See the section Instant Commands below​.

switch 12 (ON/OFF)

set to ON (enable the UPS functionality)​. Without this, the UPS will never supply power from its batteries​.

The USB-versions of the UPS contain an FTDI USB-to-serial converter chip​. It is programmed with a non-standard product ID (for example 0403:e0e3), but can still be used with the normal ftdi_sio driver​.

Use lsusb to figure out which product ID is used in your model, and replace all occurrences of e0e3 in the following examples with the actual Product ID​.

modprobe ftdi_sio
echo 0403 e0e3 > /sys/bus/usb-serial/drivers/ftdi_sio/new_id

If your system uses udev, this can be automated via an udev rule:

ACTION=="add", ATTRS{idVendor}=="0403", ATTRS{idProduct}=="e0e3", \
  RUN+="/sbin/modprobe ftdi_sio", \
  RUN+="/bin/sh -c 'echo 0403 e0e3 > /sys/bus/usb-serial/drivers/ftdi_sio/new_id'"

You can use the following udev rule to obtain a predictable device name, for example /dev/ttyUPS:

SUBSYSTEM=="tty" ATTRS{idVendor}=="0403", ATTRS{idProduct}=="e0e3" SYMLINK+="ttyUPS"

The UPS does not have a special get status command​. Instead, it continuously sends out status update messages (tens of messages per second)​. Every pollinterval, these messages are read from the serial port buffer​.

In order to react quickly on status changes from the UPS, and to prevent the serial buffer from overflowing, pollinterval should be set to a relatively low value​. The recommended value is 1 (second)​.

This driver supports the following optional settings:

max_polls_without_data=num

The serial port is polled periodically for new data (see Polling)​. If there is no valid new data after num polls, it is assumed that communication with the UPS is lost​.

The default value is 2​. Lower values may cause spurious Data stale messages, especially at startup​.

shutdown​.return

The behavior of this command depends on the line state:

• on line: after 5 seconds (or longer, if DIP switches 6-10 are not OFF), the UPS will shut off its output​. After another 5 seconds, the output is activated again​.
• on battery: after 5 seconds (or longer, if DIP switches 6-10 are not OFF), the UPS will shut off its output​. The output will stay off, until the line voltage has returned​.

shutdown​.stayoff

The behavior of this command depends on the line state:

• on line: after 5 seconds (or longer, if DIP switches 6-10 are not OFF), the UPS will shut off its output​. The output stays off, until the line voltage has been removed for at least 1 second, and has been re-applied​.
• on battery: this command behaves the same as shutdown​.return​.

Make sure that your operating system has created a serial device for the UPS​. See the section USB driver for more information​.

Next, make sure that NUT has access rights to this device file​. For example, by creating an udev rule that grants permission to the NUT user, or by adding the NUT user to a user group that can access serial devices (e​.g​. the dialout group on Debian-based systems)​.

You can verify the correct functioning of the hardware, by monitoring the serial port with a terminal program, for example picocom:

:; picocom -b 9600 -d 8 -p n /dev/ttyUPS

NUT must not be running when you do this​. You should now see a continuous stream of 5-character texts coming in, for example:

BUFRD
BA>85
DC_OK

To exit picocom, use Ctrl-A Ctrl-X​.

Untested models

Data stale messages

Matthijs H​. ten Berge