Campbell-scientific 107-L Temperature Probe Uživatelský manuál stáhnout pdf (Strana 18)

Model 107 Temperature Probe

8.3 Electrically Noisy Environments

EMF noise emanating from the ac mains power grid can be a significant source

of measurement error. 60 Hz noise is common in the United States. 50 Hz

noise is common in Europe and other regions. Depending on the datalogger

model, this noise can usually be filtered out.

The following code examples filter 60 Hz noise. The key parameters are in

bold type.

CRBasic

Therm107(T107_C,1,1,Vx1,0,_60Hz,1.0,0.0)

Edlog (except CR10, 21X, and CR7)

x: Temp (107) (P11)

1: 1 Reps

2: 1 SE Channel

3: 21 Excite all reps w/E1, 60Hz, 10ms delay

4: 1 Loc [ Air_Temp ]

5: 1.0 Multiplier

6: 0.0 Offset

Edlog (CR10, 21X, and CR7)

CR10, 21X, and CR7 dataloggers do not have 60Hz or 50Hz integration

options for the excitation channel. When using these dataloggers in electrically

noisy environments, use the AC Half Bridge (P5) instruction, which

incorporates ac noise rejection in input voltage range options. After the

measurement, convert the result to temperature using Polynomial (P55). The

following example shows the use of the P5 and P55 instructions:

x: AC Half Bridge (P5)

1: 1 Reps

2: 22 7.5 mV 60 Hz Rejection Range ;21X,CR7: 50 mV slow range

3: 1 SE Channel

4: 1 Excite all reps w/Exchan 1

5: 2000 mV Excitation ;21X,CR7: 4000 mV

6: 1 Loc [ Air_Temp ]

7: 800 Mult

8: 0 Offset

x: Polynomial (P55)

1: 1 Reps

2: 1 X Loc [ Air_Temp ]

3: 1 F(X) Loc [ Air_Temp ]

4: -53.46 C0

5: 90.807 C1

6: -83.257 C2

7: 52.283 C3

8: -16.723 C4

9: 2.211 C5

8.4 Long Cable Lengths

Long cable lengths may require longer than normal analog measurement

settling times. Settling times are increased by adding a measurement delay to

the datalogger program.

1 2 ... 13 14 15 16 17 18 19 20 21 22 23 ... 27 28

Komentáře k této Příručce

Žádné komentáře

Campbell-scientific 107-L Temperature Probe Uživatelský manuál Strana 18

Komentáře k této Příručce

Související produkty a manuály pro Měřící nástroje Campbell-scientific 107-L Temperature Probe