GENERIC_MODBUS(8)

NUT Manual

GENERIC_MODBUS(8)

NAME¶

generic_modbus - Driver for contact (direct) signal UPS devices connected via modbus remote I/O gateways

SYNOPSIS¶

generic_modbus -h

generic_modbus -a DEVICE_NAME [OPTIONS]

Note

This man page only documents the specific features of the generic_modbus driver. For information about the core driver, see nutupsdrv(8).

SUPPORTED HARDWARE¶

This is a generic modbus driver expected to work with contact (direct) signal UPS devices, connected via modbus RIO (remote I/O) either serial or TCP/IP.

The driver has been tested against PULS UPS (model UB40.241) via MOXA ioLogikR1212 (RS485) and ioLogikE1212 (TCP/IP).

More information about this UPS can be found here:

https://products.pulspower.com/ca/ubc10-241-n1.html

More information about Moxa ioLogik R1212, E1212 can be found here:

https://www.moxa.com/en/products/industrial-edge-connectivity/controllers-and-ios

The PULS UPS UB40.241 supports the following signals:

Ready contact      (DO) <--> HB
Buffering contact  (DO) <--> OL | OB
Battery-low        (DO) <--> LB
Replace Battery    (DO) <--> RB
Inhibit            (DI) <--> FSD

Digital port direction (DI/DO) assumes the device perspective

The driver’s concept is to map the UPS states (as defined in NUT) onto UPS contacts' states. The driver has an extended configuration interface implemented using variables defined in ups.conf.

HARDWARE INTERCONNECTION¶

The commission of modbus remote I/O server as well as UPS device is carried out following the corresponding instruction manuals. The following figure depicts the anticipated communication path and hardware interconnection:

+------+       +----------------+       +------------+       +------------+
| UPSD | <---> | GENERIC_MODBUS | <---> | MODBUS RIO | <---> | UPS DEVICE |
+------+  (1)  +----------------+  (2)  +------------+  (3)  +------------+


   |                   |


   +-------------------+


      HOST CONTROLLER
(1) Unix IPC
(2) RS232 | TCP/IP
(3) contacts

EXTRA ARGUMENTS¶

This driver supports the following optional settings in the ups.conf(5) file:

Generic:¶

device_mfr=value

A string specifying the manufacturer of the UPS device (default UNKNOWN).

device_model=value

A string specifying the model of the UPS device (default UNKNOWN).

Serial:¶

ser_baud_rate=value

A integer specifying the serial port baud rate (default 9600).

ser_data_bit=value

A integer specifying the serial port data bit (default 8).

ser_parity=value

A character specifying the serial port parity (default N).

ser_stop_bit=value

An integer specifying the serial port stop bit (default 1).

Modbus:¶

rio_slave_id=value

An integer specifying the RIO modbus slave ID (default 1).

States (X = OL, OB, LB, HB, RB, CHRG, DISCHRG, FSD)¶

<X>_addr=value

A number specifying the modbus address for the X state.

<X>_regtype=value

A number specifying the modbus register type for the X state

Default values:

1 for X = OL, OB, LB ,HB, RB, CHRG, DISCHRG
0 for X = FSD

Valid values:

0:COIL, 1:INPUT_B, 2:INPUT_R, 3:HOLDING

<X>_noro=value

A number specifying the contact configuration for the X state (default 1).

Valid values:

0:NC, 1:NO

Note
NO stands for normally open and NC for normally closed contact

Shutdown¶

FSD_pulse_duration=value

A number specifying the duration in ms for the inhibit pulse. If it’s not defined, signal has only one transition depending on FSD_noro configuration.

Examples for FSD signal configuration:

FSD_noro = 1
FSD_pulse_duration = 150


                     +-----+


                     |     |
inhibit pulse  >-----+     +------------------>


                      <--->


                      150ms
FSD_noro = 0
inhibit pulse  >-----+


                     |


                     +------------------------>

CONFIGURATION¶

Here is an example of generic_modbus driver configuration in ups.conf file:

[generic_modbus]


  driver = generic_modbus


  port = /dev/ttyUSB0


  desc = "generic ups driver"


  # device info


  device_mfr = "PULS"


  device_model = "UB40.241"


  # serial settings


  ser_baud_rate = 9600


  ser_parity = N


  ser_data_bit = 8


  ser_stop_bit = 1


  # modbus slave id


  rio_slave_id = 5


  # UPS signal state attributes


  OB_addr = 0x0


  OB_regtype = 1


  OB_noro = 0


  LB_addr = 0x1


  LB_regtype = 1


  HB_addr = 0x2


  HB_regtype = 1


  RB_addr = 0x3


  RB_regtype = 1


  FSD_addr = 0x0


  FSD_regtype = 0


  FSD_pulse_duration = 150

INSTANT COMMANDS¶

This driver support the following instant commands:

load.off

executes "instant poweroff"

INSTALLATION¶

This driver is not built by default. You can build it by installing libmodbus and running configure --with-modbus=yes.

You also need to give proper permissions on the local serial device file (/dev/ttyUSB0 for example) to allow the run-time NUT driver user account to access it.

OTHER NOTES¶

The generic_modbus driver intends to support generic UPS devices with contact signals through modbus TCP/RTU gateways (also known as RIO — remote I/Os). The data and signal path looks like this:

[UPSD] <--- IPC ---> [GENERIC_UPS] <--- modbus TCP/RTU ---> MODBUS-RIO <--- contacts ---> [UPS DEVICE]

On the other hand, you can setup any kind of modbus server, and configure the generic_modbus driver to connect and read or write specific registers. Your application / modbus server could then drive NUT statuses (e.g. OL, OB, HB etc) by writing over those registers.

AUTHOR¶

Dimitris Economou <dimitris.s.economou@gmail.com>