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MAS-1

Figure 3: Wiring Connection for Devices Without Current

The optional 100 uF capacitor shown in parallel with the R

duces measurement noise. It should have a voltage rating higher

than the largest supply voltage. Be sure to observe correct polarity.

The MAS-1 requires a voltage of at least 12 V. This limits the value

of R

olt since part of the total voltage drop will be across the re-

sistor. Equation 2 can be used to determine the maximum value for

olt. Table 1 shows time resistance values.

Table 1: Maximum resistance values for R

The MAS-1 sensor has several advantages over voltage-output sen-

sors, even for voltage-input data loggers.

1. The MAS-1 supply voltage does not need to be regulated for

the sensor to work properly; it can be any value between 12

and 32 volts, without aﬀecting sensor output.

2. When using a current-based sensor like the MAS-1, the signal

is not aﬀected by electrical resistance in the cable, so the sensor

output is not aﬀected by cable length or wire gauge.

3 INTEGRATING THE MAS-1

12 = 0.02R

supply

Supply Voltage

13 V

24 V

32 V

V oltM ax

at speciﬁed voltages

V olt

Load

50 ohms

600 ohms

1000 ohms

re-

V olt

(2)