This package comprises Windmill software, the 752 measurement and control unit which plugs into the PC's USB port, and free, lifetime, technical support. The 752 unit provides differential inputs to monitor resistance and voltage signals. The units also provide digital input and output, counting, and voltage or current output control. The system supports 2 wire, 3 wire, 4 wire and 4 wire compensated resistance measurement. With extra hardware you can also monitor thermocouples and strain gauge bridges.
Price: 795 GB pounds.
- Monitor resistance and voltage signals
- Switch digital outputs
- Monitor digital inputs
- Count events
- With extra hardware monitor thermocouples and strain gauge bridges
- Control voltage or current outputs
- Supports 2 wire, 3 wire, 4 wire and 4 wire compensated resistance measurement
- Includes the powerful yet easy-to-use Windmill software for Windows: no programming required
- Connect up to 8 USB units to one PC
- Choice of analogue input ranges, selected with Windmill software individually for each channel
- Alternatively, choose automatic ranging and let the software match the input signal as closely as possible
- Integrating analogue-to-digital converter reduces electrical noise
- Use Windmill to select the resolution of the A-D converter from 12- to 18-bits
- Automatic recalibration
- Comprehensive User Manual
- Free technical support for life
Resistance and Voltage Measurement
Resistance measurements are made by passing a constant, known, current through the unknown resistance, and monitoring the voltage drop across the resistance. The 752 unit has a constant current source of 1 milliamp.
When the resistance to be measured is small, the resistance in the leads to the sensors can significantly affect accuracy. However, different wiring configurations allow the lead resistance to be measured and compensated for. The Microlink 752 gives excellent results for all configurations, including 2 wire, 3 wire, 4 wire and 4 wire compensated. The most accurate results are obtained using a 4 wire arrangement. More connections are required for these arrangements than for straightforward voltage measurement. This means that you can monitor 16 voltages or 8 resistances, or a combination of the two such as 8 voltages and 4 resistances.
Digital Inputs and Outputs
The Microlink 752 provides 24 digital I/O lines, arranged in three groups of 8. Use Windmill to choose whether each group is an input or an output. You can read or set the state of each line individually. Alternatively, you can switch several channels at the same time.
The USB unit has eight 16-bit totalling counters. Each counter starts at zero and counts pulses to a maximum of 65535. You can reset a counter at any time from Windmill software. You can use the counters in two modes: accumulating count and resetting count. In accumulating count the counter keeps counting until you reset it. In resetting count the counter shows the number of pulses since the last reading.
The counters are found on 8 of the digital input and output lines. You can use any of these you don't need for counting as normal digital inputs: the counts are always maintained even if you don't plan to use them.
Thermocouples and Strain Gauges
By adding a Microlink 593 unit, which provides cold junction measurement, you can also monitor thermocouples. For strain gauges you need a Microlink 594 connection box and excitation supply.
Windmill Charting software
Windmill software is included in the package. This modular suite offers data logging, charting, alarm indication, output control and sends data to other applications like Excel. You can also add process mimic generators, sequence control and many other modules. Should you wish to program the hardware yourself, you can use the IML Tools to do so.
USB Unit Specifications
Dimensions (mm) 180 x 120 x 40
Maximum length of cable 5 m
Maximum distance from PC can be increased by
use of USB hubs
Current source 1 milliampere
Maximum resistance inputs 8
Maximum voltage inputs 16
Maximum safe input voltage:
Power supply on ±48 V
Power supply off ±33 V
Transient ±300 V
Analogue to Digital Converter:
Maximum linearity error ±0.02%
Resolution Integration Time Samples/Second
12 bits 2.5 msec 80
13 bits 5 msec 64
14 bits 10 msec 48
15 bits 20 msec 32
16 bits 40 msec 16
18 bits 160 msec 6
Voltage output 0-10.240 V
Max # voltage outputs 2
Current output 0-20.480 mA
Max # current outputs 2
Resolution 12 bits
Maximum number inputs 24
Maximum number outputs 24
(selected through Windmill in ports of 8 lines)
Power-up state all inputs
Compatibility TTL and 5 V CMOS, can be made
contact closure compatible
Range 0 to 5 V
Output capability 15 LSTLL loads
Maximum I/O speed 160 channels per second
Maximum number counters 8
Resolution 16 bits
Compatibility TTL, 5 V CMOS, can be made
contact closure compatible
Input voltage range 0 to 5 V
Maximum count speed 160 counts per second