Configure redundancy connections

Redundancy connections are point-to-point connections to the controlling station that can be activated when another connection is lost.

1. Go to IEC60870 > Redundancy connections.
2. Select Add new to add a new redundancy connection.
3. Under Memory area, select the PLC memory area for the monitoring and control buffers.

   Available areas: DT, FL (FP2SH only)

4. Specify the buffer areas.

   The settings must match the settings in the M_IEC60870_PRO7 library.

   • IEC870_RBM

     Set the start address of the memory area for the variables IEC870_RBMx or IEC870_RBMx_EM1 (x is a number from 1 to 4). IEC870_RBMx and IEC870_RBMx_EM1 specify the header of the monitoring buffer.

   • IEC870_Monitor: Set the start address of the memory area for the variable IEC870_Monitorx (x is a number from 1 to 4). IEC870_Monitorx specifies the monitoring buffer.

   • Depth of IEC870_Monitor: Set the number of records buffered in the PLC. This number corresponds to the left index of the two-dimensional array defined by IEC870_Monitorx.

   • IEC870_Control: Set the start address of the memory area for the variable IEC870_Controlx (x is a number from 1 to 4). IEC870_Controlx specifies the control buffer for incoming telegrams.

5. Enable Test frames in STOPDT to send keep-alive telegrams in the STOPDT (stop data transfer) state. (The keep-alive telegrams are sent after t3.) Default: Enabled
6. Enable Test frames in STARTDT to send keep-alive telegrams in the STARTDT (start data transfer) state. (The keep-alive telegrams are sent after t3.) Default: Enabled
7. Enable IP lock mode to set the IP address of the controlled station. Default: Disabled, the address 255.255.255.255 is set.

   You can specify individual addresses or address ranges.

   • Individual addresses: Enter one or two individual IP addresses that are allowed to open a connection. If only one address is allowed, enter the same address for IP address 1 and IP address 2.

   • Address range: Set the first and last address of the range of IP addresses that are allowed to open a connection.

8. Select Expert mode on top of this section to make timeout and other advanced settings.

   Each value must match the setting of the controlling station. Make sure the following condition is fulfilled: t2 < t1, t1 < t3, k < 15, w ≤ 2/3 of k

   • t1: Set the acknowledgement timeout for telegrams that were sent. Default: 15s

   • t2: Set the acknowledgement delay for telegrams that were received. Make sure t2 < t1. Default: 10s

   • t3: Set the delay between test frame telegrams (TESTFR) that are sent. Make sure t1 < t3. Default: 20s

   • k: Set the number of unacknowledged telegrams that can be sent. Make sure k < 15. Default: 12

   • w: Set the number of unacknowledged telegrams that can be received. Make sure w ≤ 2/3 of k. Default: 8

   • Timeout: Set the timeout for a single TCP frame. Default: 1000ms

9. Save your configuration.

   If you have changed any settings, a Save button appears in the top right corner of the screen. You can make changes in multiple pages and then save your settings.

   To reset all settings on the current page to the default configuration, select the Reset button at the bottom of the page.