The LEM501 series smart meter is front panel mounted single phase two wire multifunctional energy meters. LEM501 series smart meter adopts many advanced technologies of research and development, like microelectronic-techniques, specialized large-scale IC (integrated circuit), digital sampling and processing technology, SMT technique, and so on. LEM501 series smart meter technical performances completely conform to 《Technical specifications for single phase smart electricity meters》 from State Grid Corporation of China. LEM501 series smart meter can directly and accurately measure the load active energy consumption in the single phase AC networks of rated frequency 50Hz or 60Hz and used indoors or in the meter box outdoors. The LEM501 series smart meter have multiple configurations for option, to be suitable with the various market demands. LEM501 series smart meter have features with excellent long-term reliability, small volume, light weight, perfect appearance, easy installation, etc.

Functions and features

√ LEM501 series smart meter; Front panel mounted in 3 points for fixing. The centre-to-centre distance between the top mounting holes and the bottom one is 140 – 150 mm, which the user can select any needed distance, in accordance with Standards BS 7856 and DIN 43857.
√ LEM501 series smart meter; Metering the forward active energy, reverse active energy, forward & reverse combined active energy which is selective combination of forward and reverse active energy.
√ LEM501 series smart meter; Abundant LCD displays, with both the display of power failure and backlight display.
√ LEM501 series smart meter; Have time-of use metering, 4 tariffs, 14 intervals, 2 yearly time zones. Can set the special tariff intervals for festivals and public holidays.  
√ LEM501 series smart meter; Have settlement function. Can set the maximum 3 settlement points to work in a month. Can record the historical data for the latest 12 settlement points at most.
√ LEM501 series smart meter; Load switch inside. The meter can accord with the control signal from the receiving communication command to cut off the user’s load and realize the controlling credit function.
√ LEM501 series smart meter; Remote credit control. Can remotely realize the functions of switching on or off for the users.
√ LEM501 series smart meter; Local credit control. The user will load credit via purchasing card, adopting CPU card prepayment, to be more security and reliability.
√ LEM501 series smart meter; Can record the incidents. Record 10 times for each incident.
√ LEM501 series smart meter; Have a variety of freezing functions.
√ LEM501 series smart meter; Have alarm function of super power, power reverse, hardware failure, etc.
√ LEM501 series smart meter; Automatic cycle display, display by key, and can set all of these displays items.
√ LEM501 series smart meter; Have a RS485 communication port and an infrared communication port. RS485 communication rate can be set.
√ LEM501 series smart meter; Can add a carrier communication function, the carrier module can be inserted and pulled out, applicable to the carrier module, like Dongruan, Xiaocheng, Dingxin, etc.
√ LEM501 series smart meter; Equipped with a polarity passive impulse output terminal, conforming to Standards IEC 62053-31 and DIN 43864.
√ LEM501 series smart meter; LEDs indicate the energy impulse signal, alarm status, load switch state and carrier communication state.
√ LEM501 series smart meter; Measure the active energy consumption in one direction on single phase two wire, which is not related with the load current flow direction at all, complying with Standards IEC 62053-21.
√ LEM501 series smart meter; Direct connection. Two types of connections: type 1A and type 1B for option.
√ LEM501 series smart meter; The short terminal cover is made from the transparent PC, to reduce the installation space and is convenient for centralized installation.

Technical parameters

    Technical parameters
Model Accuracy Reference voltage (V) Current specifications (A) Working Temperature Insulation performance
LEM501XX Class 1
Class 2
127 or 230 5(30)
-25℃~+60℃ AC voltage 4kV for 1 minute, 
1.2/50us waveform impulse voltage 6kV.

Outer and mounting dimension

Outer and mounting dimension

Wiring diagram

  Wiring diagram -1 (type 1B)
Terminal Note
1 Inlet phase wire
2 Outlet phase wire
3 Inlet neutral wire
4 Outlet neutral wire
5 and 6 Cutoff control port
7 and 8 Passive energy impulse output port
9 and 10 Multifunctional signal output port
11 and 12 RS485 data communication port

  Wiring diagram-2 (type 1A)
Terminal Note
1 Inlet phase wire
2 Inlet neutral wire
3 Outlet neutral wire
4 Outlet phase wire
5 and 6 Cutoff control port
7 and 8 Passive energy impulse output port
9 and 10 Multifunctional signal output port
11 and 12 RS485 data communication port

Product configuration table

  Product configuration table
 Configuration Options Configuration Code

LCD display, with both the display of power failure and backlight display.
Have a RS485 communication port and an infrared communication port
Have PLC carrier communication function

Measure the active energy on single phase two wire
Remote credit control
Local credit control

Dimensions-Picture 1

Dimensions-Picture 2

Type 1B, Connection Diagram-1

Type 1A, Connection Diagram-2