ISO-LD Series   Isolated loadcell input board

Function Description
The ISO-LD series is a bus-type isolated loadcell input board.  The isolation inputs can operate with up to 500Vrms of common-mode voltage.
The ISO-LD series features a 12 bit analog-to-digital converter, on board 1 K bytes FIFO buffer , one loadcell signal input channel, one analog input channel, 8-channel 12-24V isolated digital inputs, 7-channel isolated open-collector digital outputs, one programmable 8-bit LED indicator to indicate the magnitude of strain gauge input signal.
The ISO-LD series board is suitable for static force measurement and dynamic force analysis. Because there are on board excitation voltage, high gain amplifier, you don*t have to buy any excitation voltage and signal conditioning module. In other words, it save your money and space. The board also have some special features, such as
1. 12-bit programmable offset voltage. Therefore  the user can cancel the DC bias and amplify the     AC signal
2.The isolated structure eliminate the ground loop noise and protect your computer.
3.On board FIFO buffer support gap-free A/D conversion under DOS and Windows
4.Except the loadcell input channel, there are a lot of digital I/O and one analog input channel .The user    can implement a measurement and analysis system.
  •  AT bus
  •  500 VDC photo-isolation protection
  •  one channel strain gauge input channel
  •  One channel analog input channel
  •  Built-in 1K bytes FIFO
  •  Excitation voltage for loadcell : 12V, 50mA
  •  Maximum gain up to 40,000
  •  Programmable 12 bit resolution ,DC offset voltage (0~5V)
  •  Second order low pass filter build-in
  •  Direct connection to strain gauge type loadcell
  •  8-channel 12-24V isolated digital input
  •  7-channel isolated open-collector digital output
  •  Programmable 8 bits LED indicator.
  • Command set programming
  •  Strain gauge type loadcell measurement
  •  Dynamic force on line monitoring system .
  •  Dynamic pressure measurement
Ordering Informatin 
ISO-LDH : 12-bit Load-cell input Board (High Gain)
ISO-LDL : 12-bit Load-cell input Board (Low Gain)
Option :
DN-25 :  9-pin , 25-pin D-sub Connector Screw Termianl Board
S-50 : S-type Load-cell 

Software :
  • NAPWIN : Software Toolkit for Windows 95/98
  • NAPWNT: Software Toolkit for Windows NT 4.0
  • NAPVIEW: Software Toolkit for LabVIEW

  • NAPX:ActiveX Control (OCX) for Windows 95/98/NT
Analog Input Specifications
Channels 1 loadcell input channel & 1 analog input channel 
Resolution 12 bits 
Conversion rate  16 KS/s max 
Nonlinearity +/- 0.01 % 
Gain error 0.005% of reading maximum 
Input Impedance 10,000MW||6pF 
bias current +/- 3 nA (maximum) 
Input offset current  +/- 2 nA (maximum) 
CMRR 90 dB ( Minimum) 
Recommended warm-up time  10 minutes 
sample & hold   On chip 
ISO-LDH Input Range
Analog input range 0~10V , 0 ~1V , 0~0.1V , 0~0.01V
Strain Gauge input range 0 ~ 37.5mV
Resolution   12-bits
Gain Input range 400 0~37.5 4,000 0~15 40,000 0~12.75 
ISO-LDL Input Range
Normal input range 0~10V, 0~5V, 0~2.5V, 0~1.25V 
Loadcell input range 0 to 37.5mV 
Loadcell offset voltage adjustment  0 to -5V, 8 bit 
Resolution   12-bits
Gain Input range(mV)  400 0~37.5 
8,00 0~25 
1,600 0~18.75 
3,200 0~15.625 
Loadcell Offset Voltage Adjustment  0 to -5V, 12 bit resolution 
Digital I/O
digital input  8 photo-isolated 12~24V 
digital output  7 isolated open-collector (100mA) 
output  8 TTL/LED 
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There are a lot Strain Gauge type LOADCELL sensors available for the ISO-LD board. The user can find the S -50 Loadcell from options to match ISO-LD board to implement a loadcell measurement starter kit.


Capacity 60Kg 
Rated Output 2 mV/V 
Total error 0.05% 
Repeatability  0.03% 
Creep 0.05% / 30 min 
Resolution 1/10,000 
Input Resistance 410 +/- 15
Output Resistance 350 +/- 5
Max. Excitation Voltage  20V 
Compensated Temperature Range -10*C ~ 50*C 
Safe Temperature Range   -20*C ~ 70*C 
Temp. Effect on Rate Output : 0.03% Load/10*C 
Zero Balance 5% R.O.
Safe Overload Rating 150% 
Cable Length  2M 
Cable connection Input:Red(EX+), Black(EX-) Output : Green (LS+), While (LS-) 
Power Requirements +5V @400mA(max) 
General Environmental
Operating temp 0-50C 
Storage temp  -20*C  to  70*C 
Humility  0 to 90%  non-condensing 
Dimensions   190 mm  x 105 mm