Product Overview 
 Based on providing a simple and practical solution for GPRS communication needs, communication Kechuang developed DLK-D230 GPRS DTU. It is embedded in the TCP / IP protocol stack to address the user in the use of common modules without TCP / IP protocol stack and the client systems to be embedded TCP / IP limitations, the use of the GPRS network to achieve a reliable transparent transfer of data information. 
 While simplifying the interface design and external servo circuit is more suitable for harsh industrial field. RS-232 (Model DLK-D230), RS-485 (Model DLK-D231), TTL (Model DLK-D232)-level interface, using simple AT + i commands, you can complete end to end reliable data communication, a very greatly reduced development time and maintenance of user workload. 
 In addition to the product flexibility to implement a variety of equipment access, installation simple. Apply to the use of single-chip serial communications data collection and transmission system, PLC or RTU as well as industrial machine, it allows customers to existing wired serial devices need to change immediately into a wireless network communications equipment. To reduce the input of the system update. 

 Industrial applications 
 Power: the city distribution network automation system, real-time monitoring and automatic compensation grid, power remote automatic meter reading 
 Highway weather station: on the highway the temperature, humidity, wind direction, wind speed and spatial resolution of the data transmission 
 Oil: Oil pipeline temperature real-time online testing, field data collection 
 Coal: Coal mine real-time online testing 
 Financial: POS machine networking 
 Communications: telecommunications room power environmental monitoring, communications, maintenance personnel line data inquiries 
 Public Security: public security, 110, traffic police vehicle monitoring and dispatching, police mobile data (identity crime files, etc.) query 
 Heat: real-time monitoring and maintenance of thermal systems 
 Industrial: Industrial remote sensing, telemetry, remote control information return 
 Weather: Weather data collection and transmission 
 Water: hydrological monitoring 
 Life: real-time data acquisition Gas regulator station automatic control, water, sewage pipes, gates and water to maintain real-time monitoring 
 Transportation: street surveillance, traffic flow information, GPRS / SMS / GPS motor vehicle monitoring and dispatching system; bank armored cars, monitoring and dispatching postal truck 

 Features 
 ◆ built QUECTEL M20 wireless module, compatible with all AT command set 
 ◆ smallest of similar products for embedded integration 
 ◆ and have the power saving mode, suitable for mobile devices 
 ◆ scalable update Firmware, better transmission quality 
 ◆ enables point to point, multipoint, and APN line so flexible networking, support two modes of CLIENT and SERVER 
 ◆ heart model based on PING function to maintain the link flow 
 ◆ Low power consumption: in a sleep state when the current is 3mA 
 ◆ supports three languages ??encoded transfer rate 
 ◆ Embedded TCP / IP protocol stack to support multiple protocols, TCP, UDP, DNS, PPP, DHCP, etc. 
 ◆ highly integrated GPRS and TCP / IP technology, the Internet and GPRS networks combined organic 
 ◆ completely transparent transmission mode, data radio can completely replace the original system without any changes, system updates to minimize the input 
 ◆ support ALWAYS ONLINE (always online) mode, support dropped reconnection 
 ◆ support GPRS data transmission line, telephone wake-up, remote reset and upgrade 
 ◆ Transparent mode, short connectivity, automatic timed release and link re-activated with 
 ◆ Real-time dynamic refresh, effective solution to the wireless network "false connection" phenomenon 

 Technical parameters 
 RF characteristics: 
 The use of GSM phase 2 / 2 + standards 
 Quad-band: GSM850MHz EGSM900MHz 
 DCS1800MHz PCS1900MHz 
 Transmit Power: 
 Class4 (2W) at GSM850 and GSM900 
 Class1 (1W) at DCS1800 and PCS1900 

 Electric power consumption: 
 Input voltage: DC5 ~ 25V (standard 9V power supply) 
 SIM card operating voltage: 3V/1.8V 
 Current consumption: 
 Talk mode: 310mA (average) 
 Sleep mode: 3.0mA (max) 
 Idle mode: 10.0mA (max) 

 Features: 
 SMS: MT, MO, CB and PDU mode 
 Messaging content: support for digital, voice, SMS and fax 
 Module reset: The AT command or power-down reset 
 Audio decoding standards (three rates): 
 Half speed (ETS 06.20) Full Speed ??(ETS 06.10) 
 Enhanced full-speed (ETS06.50/06.60/06.80) 
 Maximum transfer rate: 14.4KBPS 

 Volume: 
 Without mounting holes and interface: 64 * 46 * 18.5mm 
 With mounting holes and interface: 78 * 66 * 18.5mm 
 Weight: 200g 

 Appearance: 
 Shell package: 
 Good electromagnetic shielding and metal shell, durable; anti-electromagnetic interference, extremely high-temperature heat capacity 
 Interface: Standard RS-232/RS-485/TTL level, DB9 Interface 
 Antenna: 50ohm/SMA/Fem 

 Environment: 
 Operating temperature: -40 ℃ ~ 65 ℃ 
 Automatic shutdown:> / +70 ℃ 
 Storage temperature: -50 ℃ ~ 85 ℃ 
 Humidity: ≤ 90% 
 Magnetic compatibility: Electrostatic discharge immunity test level: 3 
 Radio frequency electromagnetic radiation: the immunity test level: 3