Bộ điều khiển hiển thị cân, Schenck weighing display controller VEG20610/VDB20600

2, environmental parameters
  1. Storage temperature - 40 ° C - +70 ° C;
     Operating temperature -10 ° C - +50 ° C;
  2. Maximum relative humidity: 95%
3, the power supply
  220VAC+10%~—15% 50Hz
  Fuse 0.5A
  EMI/RFI filter
4, weighing sensor
     The instrument provides 10VDC, 200mA excitation power supply, and can be connected in parallel with 4 load cells.
     Sensitivity, 0.5mV/V-3.5mV/V
     Maximum input signal 33mV
     Load cell shield grounding
     Use the excitation compensation circuit jumper to select local or remote compensation when the cable distance is greater than 60 meters (not more than 900 meters)
5, the motherboard digital input port
   The instrument main board provides three programmable input ports to receive dry contact switch signals.
6, the motherboard digital output port
   The instrument main board provides 3 programmable output ports and 24VDC open collector output, which can directly drive the control relay.
7, communication board
   The instrument can be equipped with a communication board. It can use standard RS-232, RS-485 serial interface and host computer communication board to collect instrument data and operate the instrument, and has two-way communication function.
8, the main performance
Four lines display, select through menu
 5 status indicators
 Current output of material flow or load
 Pulse output of total material weight
 Automatic zero adjustment
 Automatic zero tracking
 Photoelectrically coupled digital inputs and outputs
Alarm and fault prompts
Communication function: RS232, RS485 multi-station communication network
One way process control mode: PID control output
9, the main function
    All functional software is solidified in the memory chip. When the user installs an optional expansion board or the operator selects through the keyboard, the controller will automatically open the corresponding function.
   (1) Measurement function
     a, instantaneous flow calculation 
    The load cell output unit weight signal is multiplied by the speed sensor output unit belt speed signal. This result is instantaneous flow.
     b, weight accumulation
The cumulative amount is the total weight of the unit length and the running length, and then converted into engineering units.
C, automatic zero adjustment and automatic adjustment interval
By defining the number of belt turns and belt length is the basis for automatic zero adjustment and automatic adjustment interval.
    To accurately calculate the length of the belt, the controller calculates the number of pulses from the speed sensor. When the required number of pulses is accumulated, the controller ends the calibration test, compares the theoretical value with the actual value, and calculates the calibration constant.
     d. Automatic zero tracking  
    When the belt is running, the flow rate is lower than the predetermined value, and the controller performs automatic zero adjustment according to the following steps.
    -- Wait for half of the test cycle (“Z” will be displayed)
    - Complete a zero test
    - Complete automatic zeroing of a test cycle
    - As long as the flow value is lower than the automatic zero tracking tracking value, the meter will repeat the above steps
e, one input, two current output signals
    Optional input/output expansion board for one voltage/current input and two current output signals
(2) Monitoring function
    Status prompt
    Process alarm
    Setting error
    Equipment failure
    High flow, low flow, high load, low load alarm
(3) Automatic control of feeding function 
    The weighing controller provides an independent control current loop. The control current loop is usually used to control the feed amount. The control method is
    —— PID=proportional + integral + differential
    The controllable process variable is the feed amount, and the flow setting can be set via keyboard input or external analog signal. The control output is a 4-20 mA current loop.