Monitoring

The Poseidon2 and Damocles2 works as a TCP Server at port 502 (Modbus standard). The Modbus/TCP communication takes place using the given addresses. For details, see http://www.modbus.org .

Caution: Modbus/TCP implementation support requires setting the " Slave ID " variable to number 2. Check the setting of this variable in case you are enable to establish a connection. (The actual name may differ in your software – it used to be an address to distinguish multiple devices on a RS-485 line in case of Modbus/RTU).

What you can find in this application note:

• We describe how to properly setup Modbus Poll program version 3.20
• You find out what is possible to read via Modbus/TCP protocol

Notice: Modbus Poll application version 3.20 in its unregistered version works only for 4 minutes after launch. It is necessary to restart the program after to run it again.

Mapping of variables for the Modbus/TCP protocol

Remote INPUTS

Remote OUTPUTS

Sensors

The Poseidon2 and Damocles2 works as a TCP Server at port 502 (Modbus standard). The Modbus/TCP communication takes place using the given addresses. For details, see http://www.modbus.org .

Caution: Modbus/TCP implementation support requires setting the " Slave ID " variable to number 2. Check the setting of this variable in case you are enable to establish a connection. (The actual name may differ in your software – it used to be an address to distinguish multiple devices on a RS-485 line in case of Modbus/RTU).

Program Modbus Poll & Damocles MINI

Dry contact inputs - model MINI

Connect the Damocles MINI unit to ethernet and power supply. Launch Modbus Poll application (mbpoll.exe file). In setup menu select option Poll Definition (keyboard short cut F2).

Picture a - Input setting

Setting of inputs in Modbus Poll program (Picture a)

• Slave ID: 2
• Function: definition of running function 02 INPUT STATUS for monitoring of input states
• Address: definition of used variables that will be loaded (for addresses see figure bellow). Beginning at the address 100 - ending at the address 103
• Length: length of loaded variables
• Scan Rate: delay between two following loadings
• Auto Read Enable: to enable automatic reading of values
• Click OK button to confirm

 

Picture b - Network parameters setting

Addresses of inputs in terms of protocol are configured, now set up connection to device itself.

• In Connection menu select Connect (keyboard short cut F3)
• Select TCP/IP
• Set up device IP address and Port (standard is 502)
• Push OK button to confirm

Application is now connected to selected device and in periodic interval loads input values (see the picture c).

 

Picture c - Values loading

Picture d - Damocles MINI - WWW page

>> Damocles MINI
Download and application of Modbus Poll + examples

 

Binary outputs (Damocles MINI)

Open Poll Definition menu to control binary outputs.

Picture e - Output setting

• Slave ID: 2
• Function: definition of running function 01 COIL STATUS for monitoring of output states
• Address: defines the address of used variables that will be logged (for addresses see figure bellow). It begins at the address 200 - ending at the address 201
• Length: number of loaded variables
• Scan Rate: delay between two loadings
• Auto Read Enable: to enable automatic reloading
• Click OK button to confirm

To control binary inputs select option 05 in function menu: Write Single Coil (short cut F7).

Picture f - Output control

You can safe setting of Poll Definition to mbp file to simplify your work. Any time you need it simply load the saved setting.

 

Modbus Poll & Poseidon2 4002

Temperature sensor - model4002

Open Poll Definition in menu.

• Slave ID: 2
• Function: definition of running function 04 INPUT REGISTER for monitoring of output states
• Address: defines address of used variables that will be loaded (for address see figure above).
  • Andrea 100 - number of sensors
  • Addressed 101 - current value
• Length: number of logged values
• Scan Rate: delay between two readings
• Auto Read Enable: to enable automatic reloading
• Click OK button to confirm

Picture ch - Setting of temperature sensor

Two lines are displayed. The first line shows number of connected sensors and the second current temperature with an accuracy of 0.1° C. Save your setting to mbp file to simplify work with Poll Definition. In case you need it, simply load saved setting.

Industrial Bus (RS-485)

• Maximum cable length: 1000 m total
• Number of devices on the bus: Poseidon + up to 31 devices
• Power: 12V/120 mA supplied by the bus, can be boosted with an external adapter (through a S-Hub or a Spider unit).
• Cable type: UTP (2 or 3 pairs)

Topology 1: Basic

• The bus leads via a 4-wire connection from the Poseidon 1250 unit to two daisy-chained sensors, Temp-485 and HTemp-485. Two twisted pairs are used by the connection.
• A S-Hub unit is daisy-chain-connected via the RJ45 jack after the second sensor, using a 4-wire connection from the HTemp-485 sensor. The brown pair is used for power, the blue pair for data.
• Temp-485 and HTemp-485 sensors are connected to the S-Hub connectors 1 through 3 with 6-wire connections (brown pair for power, blue pair leads the bus to the device, green pair back from the device).
• Connector 4 of the first S-Hub unit is used to connect a Spider converter with a patch cable. The Spider unit is used to connect three Temp-1Wire 10m temperature sensors and one door contact (the contact is connected to the blue pair of the RJ45).
• A second S-Hub connects to the Spider unit output via a patch cable.
• Its connectors 1 through 3 are used to connect the Temp-485 and HTemp-485 sensors with 6-wire connections (brown pair for power, blue pair to the device, green pair back from the device).
• Connector 4 is used to connect a Temp-485 sensor with a 4-wire connection (brown pair for power, blue pair for the A/B signals of the bus).
• Termination is enabled at the Temp-485 sensor using the “TERM” jumper.

Topology 2: Connecting 10 sensors to IT Bus

Eight temperature sensors and two humidity sensors are connected via the IT Bus (RJ12) to a Poseidon 1250 unit. The 10 sensors are connected using two T-Box hubs and one T-Box2 unit.

• Bus used to connect the sensors: IT Bus

• Total bus length: 10m
• Maximum number of sensors: 10
• Sensors used:
  • 2x Humid-1Wire 1m
  • 8x Temp-1Wire 1m 
• Accessories used:
  • 2x T-Box
  • 1x T-Box2

Conclusion:

This solution is limited by the maximum IT Bus length. It is suitable for applications that use 1 to 10 sensors at one place (one location, 19” rack cabinet, etc.)..

Topology 3: Poseidon Spider – bus converter

The solution combines the properties of both buses. Two Spider units are far apart, connected via a Patch cable with RJ45 modular jacks. Both Spider units connect to four temperature or humidity sensors, each with a 10m cable. One Temp-485 sensor is located at the end of the chain and terminates the bus.

• One Temp-1Wire temperature sensor with a 10m cable is connected directly to the Poseidon unit to the RJ12 jack.
• Six temperature sensors and two humidity sensors are connected via the IT Bus (RJ12) to the Spider units. Each sensor is connected with a 10m cable.
• Two Spider units are connected to Poseidon 1250 with a standard RJ45 Patch cable using the Industrial Bus. Bus length is limited to 1000m.
• The Spider unit comprises 4 inputs for external sensors and supports one sensor per connector – for a maximum of 4 sensors.
• The Industrial Bus is terminated by connecting a Temp-485 sensor with termination enabled over a 4-wire connection. The Spiders have mutually different addresses and are set to the “middle” mode.

• Bus used to connect the sensors: IT bus, Industrial Bus
• Total bus length: 1000m + 9x 10m
• Maximum number of sensors: 40
• Sensors used:
  • 6x Temp-1Wire 10m
  • 2x Humid-1Wire 3m
  • 1x Temp-485
• Accessories used:
  • 2x Poseidon Spider
  • 2x RJ45 Patch cable 300m (RJ45-RJ45)
  • 1x RJ45 TP cable 300m (RJ45-4 pins, “LAST” wiring)

Conclusion:

This solution is not limited by the IT Bus length. The Spider units can be up to 1000m apart. The solution is suitable for large-scale applications with many sensors (e.g. server rooms).

Topology 4: Using the Industrial Bus – star topology

This solution demonstrates a star-like connection of sensors to the Industrial Bus using an S-Hub unit. The S-Hub is the central point that connects individual sensors. The maximum bus length decreases to 500m because the cable length of all sensors connected to the S-Hub must be counted twice. A Temp-485 sensor with termination is at the end of the bus.

• One Temp-1Wire temperature sensor with a 10m cable is connected directly to the Poseidon unit, to the RJ12 jack.
• The Industrial Bus connects to the S-Hub input via a RJ45 patch cable. At the same time, the cable powers the sensors as well as the S-Hub; extra power can be supplied by an external power adapter.
  • Sensors must be connected to the S-Hub in a sequence, starting from output No. 1. Outputs cannot be skipped. (For instance, connecting outputs 1,2,5,6 while leaving outputs 3 and 4 unconnected will not work.)
• First three temperature (Temp-485) and temperature/humidity (HTemp-485) sensors are connected in sequence to the first three outputs. An RJ45 / 6-wire cable, wired according to the “MIDDLE” version, is used to connect them.
• The Spider unit is connected with a Patch cord. The Spider connects four Temp-1Wire sensors at 4x 10m distances. The Spider unit is in the “MIDDLE” mode.
• The Industrial Bus is terminated at the Temp-485 sensor connected to the S-Hub at position No. 5. The connecting cable is wired according to the “LAST” version, termination is enabled at the sensor (Term=On).

Topology 5: Using the Industrial Bus – daisy chain

The solution demonstrates daisy-chain linked sensors on the Industrial Bus. Note the distances between sensors. The Spider unit connects four local temperature sensors. At the end of the bus, there is a Sens-UI voltage and current sensor with termination enabled.

• One Temp-1Wire temperature sensor with a 10m cable is connected directly to the Poseidon unit to the RJ12 jack.
• Two HTemp-485 temperature/humidity sensors are connected at the beginning of the bus, using a 4-wire cable connected to the terminals.
• The bus continues to the Temp-485 temperature sensor, still with 4 conductors.
• The Temp-485-Pt100-Cable uses a 4-wire connection as well. The temperature is measured by a Pt100 sensor mounted on a 2m silicon cable.
• The next Temp-485-Pt100-2xDIN converter, mounted on a DIN rail, uses a 4-wire connection. Two external Pt100 thermometers measure two temperature values.
• The following Temp-485-Pt100-Box sensor, designed for external environment, includes a probe for precise temperature measurement. 4-wire connection.
• The Spider unit is, on the contrary, connected via a RJ45 jack. The Spider connects four Temp-1Wire sensors located 4x 10m away.
• Please note the crossing of cables. It is necessary to respect the input and output designation of the RJ45 jacks. The Spider is in the “middle” mode.
• The Industrial Bus finally leads, via a 4-wire connection, to a Sens-UI sensor that measures external voltage and current.
• At this point, the bus is terminated by an external 120 Ohm resistor between the A and B pins.

   

Sources of false alarms

• Contact bounces
• Oscillation of the reading around the threshold
• Changing the connections

The problem is particularly bothering if you use Poseidon with a GSM modem that sends a text message (SMS) to your mobile phone upon each and every alarm.

Poseidon supports two functions to avoid false alarms:

• Alarm Notification Delay
• Hysteresis Idle Range

Alarm Notification Delay

The Alarm Notification Delay function prevents an alarm alert from being sent if the alarm lasts only for a very short time. The same delay is applied to alarm activation and alarm deactivation alerts.

• Blue color indicates the behavior when Delay [s] = 0.
• Orange color indicates the behavior when Delay [s] = 20.

Hysteresis / Idle range

The Hysteresis setting defines a tolerance band for suppressing alarm alerts. The function prevents multiple alarm alerts if the reading oscillates around the specified threshold. The range is configured independently for each sensor.

The figure demonstrates two cases. Without the hysteresis idle range of 5°C, the alarm raised in point 8 would end in point 9; however, the hysteresis function keeps the alarm active until the temperature reaches the upper limit of the tolerance band (point 10): 5℃ + (–15℃) = –10℃.

• Hysteresis = 5°C:   
  The unit sends 3 e-mail (SMS) messages
  Alarm active in points 0..4,  8..10, 12 and beyond
   
• No hysteresis (0°C):   
  The unit sends 8 e-mail (SMS) messages
  Alarm active in points 0..1, 2..3, 8..9, 12..13, 14 and beyond

Technical description

• Power consumption is measured by ABB DHM13007 and DBM23000 M-Bus digital power meters.
• One phase ABB ODIN single power meters are connected through the OA1408 serial to M-Bus converter.
• Each electricity meter provides voltage, current, power factor, energy, kWh and other available values.
  All values are readable via SNMP, Modbus/TCP, XML and other protocols.
• Electricity meters are connected by M-Bus to HWg-PWR 25 (smart M-Bus to LAN gateway).
• Autodetection can identify connected M-Bus meters.
• All M-Bus meters are powered from the HWg-PWR 25 device.
• The HWg-PWR smart M-Bus to ethernet gateway sends an alarm in the event of failure or value out of a specified range (E-mail, SNMP Trap, SMS over SMS GW).
• You can connect an external SMS Gateway for simple SMS alerting without any software.
• PDMS can export energy consumption to MS Excel even for every single minute.

HWg-PDMS software: Energy in graphs & MS Excel

• HWg-PWR 3/12/25 gateway can be connected to the PDMS software directly over LAN or by email.
• Variables can be analyzed in the HWg-PDMS software.
• Graphs can be viewed directly in HWg-PDMS.
• Measurements can be exported using the XML interface.
• Measurements can be imported to MS Excel for further processing.