Each WAN interface of a TIM can be operated with the function "Station", "Node terminal" or "Control center" (exception: the function "Node terminal" is not available on the TIM 3V-IE, TIM 3V-IE DNP3, TIM 4R-IE DNP3, and the function "Control center" is not available on the TIM 3V-IE DNP3 and TIM 4R-IE DNP3). This enables the construction of the type of hierarchical communication structures required in classic WANs.

On IP-based networks, in which each partner has equal priority, this classification can be dismissed. The transmission via GPRS, however, represents an exception, as without special GPRS provider contracts, direct communication from GPRS station to GPRS station is not possible. This can be solved by "rerouting" through a control center TIM, as in a classic WAN with cross-traffic on a dedicated leased line or wireless. In this case, the interfaces of the participating TIMs are to be set to the function "Control center" or "Station" in an IP-based network as well so that the correct path from "Station" to "Station" will be found automatically through the "Control center".

The TIM independently processes the data traffic via the network connected in each case and it does this according to the store-and-forward principle. For this purpose, the module has its own processor and a RAM for buffering data messages (depending on the type of TIM, between 10,000 and 56,000 message frames). The saving of the messages prevents a loss of data if the communication link is faulty or the partner fails. It also helps to reduce connection charges in dialup networks. If the optional backup battery is used for the TIM 4R-IE or TIM 4R-IE DNP3, stored data frames are not lost even if the 24 V supply voltage fails.

Reading and writing data that the TIM is to send or receive for a CPU can also be done with:

• TD7onCPU, the SINAUT TD7 software for the CPU, applicable to S7-300- and S7-400-CPUs as well as C7 compact control systems:
  The SINAUT program in the CPU, configured with modules from the SINAUT TD7 library, acquires the process data to be transferred, checks it for changes and transfers the changes to the TIM for transmission over the WAN. Messages received without faults by the TIM via the WAN are forwarded to the local CPU. A block that has been integrated there for evaluating the specific message frame ensures that the received information is output to the outputs or data areas configured in the block.
  This block library cannot be used in conjunction with TIM 3V-IE DNP3 or TIM 4R-IE DNP3.
• TD7onTIM, the SINAUT TD7 software integrated in the TIM (not present in the case of the TIM 4R / TIM 4RD), can be used with S7-300 CPUs and C7 compact control systems:
  The TD7onTIM program configured by the user reads the process data to be transferred directly from the memory areas of the CPU inserted into the S7-300 rack (inputs, bit memories, DBs), checks them for changes and then transfers the changes to the send buffer of the TIM for transmission over the WAN. Data from message frames received without fault by the TIM via the WAN are directly written by the TIM into the configured memory areas of the CPU.

If required, the data acquired by "TD7onCPU" or "TD7onTIM" can be tagged with a time stamp and the "normal" or "high" priority identification for transmission over a chargeable network, e.g. dial-up or GPRS. "TD7onTIM" also allows extremely important data to be labeled with the priority "Alarm". These have priority over all other message frames saved in the send buffer, i.e. they are transmitted before the others.

If the local SINAUT station is a control center PC, operator inputs are recorded by the PC program in accordance with the data message frame configuration, and transferred with the configured destination address to the TIM. Messages received without faults by the TIM via the WAN are forwarded to the control center PC. Evaluation of the relevant frame is handled by the control system software.

The TIM first saves the data to be sent in its RAM buffer. The subsequent response of the TIM on sending this data is explained in the two following sections.

Communication via a classic WAN

The response of the TIM on sending the data depends on the WAN type and the TIM function that is set on the WAN interface:

• Dedicated line, wireless network;
  if the interface is operated in the function "station" or "node terminal", the TIM waits to be polled by the control center before it transfers the stored data message frames. If there are no message frames available, polling is simply acknowledged.
  If operated as a "control center", the TIM sends one of the message frames saved in the buffer following each completed poll + response (standard setting). If a larger number of message frames is to be sent between two polls, this can be specified when the TIM is configured.
• Dial-up network;
  in "station" or "node terminal" mode, the TIM will initially not be active in the case of data with "normal" priority. In the case of data of "high" or "interrupt" priority, the TIM will immediately try to establish a link to the addressed partner in order to transfer the data. If data of "normal" priority are also available in the TIM buffer at this time, these will also be transferred. Data of "interrupt" priority will always be transferred first. The data of "high" and "normal" priority will subsequently be transferred in accordance with the FIFO principle, i.e. regardless of their respective priority.
  If the interface is set to the "control center" function, the TIM will always try regardless of priority to establish a link to the addressed partner and to transfer the data.

The SINAUT ST7/ST1 protocol can be used for all WAN types and TIM functions. The DNP3 protocol only allows use of dedicated lines and wireless networks in the function "Station". The operating mode used depends on the type of WAN:

• Data exchange via dedicated line and wireless network usually takes place in "Polling" mode. In wireless networks with SINAUT ST7 protocol, the operating mode "Polling with time slot method" can be selected if required.
• On dial-up networks (only with SINAUT ST7/ST1 protocol), data exchange always takes place in "Spontaneous" mode.

Communication via an IP-based network

For transmission via an IP-based network, a permanent S7 connection via which the partners exchange the data packages is established in each case between two TIMs or between one TIM and the control system.

PG communication

PG communication allows all S7 stations connected to the LAN, e.g. Industrial Ethernet, to be remotely programmed. With the aid of S7 routing it is possible to use programming device communication across networks.

Cross-network PG communication functions with the SINAUT ST7 protocol for all classic and IP-based WANs. Remote programming and remote diagnosis of the stations connected to the WAN (CPUs and TIMs) is therefore possible.

In IP-based DNP3 networks, PG communication does not take place via the protocol itself, but via a separate PG connection (TCP/IP connection).

Diagnostics & service

The "SINAUT Diagnostics & Service Tool" provides comprehensive diagnostic functions and tools for commissioning and troubleshooting, e.g.:

• Operating status of the TIM
• Module status of the TIM
• General diagnostic information
• Diagnostics buffer of the TIM
• Status of the connections to local and remote communication partners (CPUs, TIMs, control systems)
• TIM frame monitor for recording the frame traffic
• Disabling and enabling stations in the dedicated line or wireless network, e.g. during commissioning

TIM modules with Ethernet interface also offer the following:

• Status and fill level of the send buffer, for each communication partner separately
• Diagnostic information regarding TD7onTIM

Configuration

The "SINAUT ES" configuration software is used for configuring the TIM. Modules from the "SINAUT TD7 module library" must be used for configuring the SINAUT program in the CPU (TD7onCPU). Both software packages are part of the SINAUT ES engineering software. The SINAUT ST7 configuration software requires that STEP 7 V5.5 with SP2, or higher, is installed.

The configuration data – like the interface functionality, protocol, addresses of the communication participants, the telephone numbers of the partner in the dial-up network, etc. – that are required in each case can be saved in the Flash EPROM on every TIM or, in the case of the TIM 4R-IE or TIM 4R-IE DNP3, also on the optional plug-in C-PLUG. On all TIMs with Ethernet interface, the configuration data can also be stored on the memory card (MMC) of the CPU when installing in an S7-300 rack or in a C7 control system. The TIM can be replaced without the need for a programming device if the configuration data is saved in the CPU or in the C-PLUG.

Approvals

All TIM communication modules have the approvals CE, FM, ATEX, cUL508 (= UL508, CSA22.2) and cUL HazLoc. The TIM 3V-IE and TIM 4R-IE modules are also available in a SIPLUS version for the extended temperature range (-25 ... +70 °C).