Mid Device

Sensors without locating send the dynamic websites directly into the network (see figure on the far right). If the type designation ends with an L, the sensors have sub-microsecond time synchronization. Together with the Mid Device (red), it is possible to set up sensor networks that allow location of the AE sources. The mid device receives the measurement data, stores it on an SSD and generates the dynamic web pages.

Mid Device 2G.MD.54V for the source location
Technical Specification
SSD
1 TB
Data Transfer to Sensors
IEEE 802.11b/g/n or
IEEE 802.3 Clause 25
Data Transfer to Net
IEEE 802.11ac or
IEEE 802.3 Clause 40
IP Address
Fixed, Auto, DHCP
Power Supply
12 V oder 54 V DC
Power Consumption
< 12 W
Mass
1220 g
Dimension
160x165x52 mm3
Outer Casing
Aluminum
Protection Class
IP 40, IP 54 or IP 67

Application example tank floor test:

The tank floor test is a typical example of the use of mobile acoustic emission systems. The aim is to locate weak points in the tank bottom, which otherwise can only be detected after emptying and cleaning the tank. In the lower part of the tank shell, sensors are installed in two rows on top of each other in order to filter out and locate events from the ground area. If one uses conventional detection systems with central signal processing unit, the sensor cables must reach around the storage tank. Due to the relocation of important system components into the sensors, only cable lengths are needed that correspond to the sensor distances. The WLAN types do not need any cables, but three mid devices because the tank shields the electromagnetic waves. The data exchange between the mid devices and the network takes place either in the 5 GHz band or via Ethernet.



With a tank diameter of 25 m, the sensor type 2G.PoE.L reduces the total cable length for a 32-channel system from 2240 m to 200 m. Depending on the network structure, the sensor type 2G.WiFi.L achieves a reduction from 2240 m to 80 m or does not require any sensor cables. The comparison refers to a system with purely central signal processing.