The MT16-4L mezzanine is designed to measure the resistance of resistive sensors using a four-wire measurement circuit over sixteen channels (sixteen-channel digitizer). The MT16-4L mezzanine is installed on the mezzanine carrier - the NM-M module and connected to it via a local information highway. Up to four different types of mezzanines can be installed on the NM-M module. The NM-M module, together with the mezzanines installed on it, forms the VXI module of size C-1 and is used to create information measuring VXI systems.
Four MT16-4L installed on the NM-M module form a 64-channel digitizer.
The mezzanine performs resistance measurements by scanning sixteen independent channels in a single or cyclic mode. When the measured value exceeds the measurement range, an interrupt request is issued. The measurement results can be averaged, which allows for the time interval chosen by the user and significantly reduce the influence of random errors on the measurement result.
The mezzanine inputs are connected to the measured sensors via relay contacts. This allows you to untie the M-module from the control object without disconnecting the cables and without removing the supply voltage from the mezzanine.
The software correction "0" and the mezzanine operability check are performed when the measuring circuits are connected to its inputs and do not change their state.
The measuring channels are galvanically isolated from control circuits, power circuits, and common VXI trunk circuits. The electrical strength of the isolation of the galvanic isolation is not less than 200 V. The resistance of the galvanic isolation is not less than 20 MOhm.
|Four-wire DC resistance measurement over sixteen independent channels||The period of obtaining measurement results (sampling period) is set the same for all channels involved in the measurement, in the range from 302 μs to 16.777214 with a step of 1 μs.|
DC Resistance Measurement Ranges
Values of interrogation currents flowing through measured resistances
Limits of permissible basic relative error of DC resistance measurements at the minimum sampling period (obtaining measurement results) and at ambient temperature (20 ± 2) °С,%
For interrogation currents (227 ± 5) μA:
Limits of permissible additional relative measurement error of instantaneous voltage values with a minimum sampling period for all measurement ranges,%
± 0,002 × T,where T is the deviation of the ambient temperature from the value of 18 ºС (for the temperature range from plus 5 to plus 18 ºС) or from the value of 22 ºС (for the temperature range from plus 22 to plus 40 ºС).
|Dielectric isolation dielectric strength not less than 150 V. Galvanic isolation insulation resistance not less than 20 megohms|