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Water Log H-377 Temp Probe


PNBOR Dec 14, 2009 09:18 PM

Just wondering if anybody is using this sensor with a CR10X logger? If so was wondering if you could supply programming instructions.

Thanks


Sam Dec 16, 2009 03:38 PM

PNBOR,

I'm hoping someone else jumps in on this, but here's a crack at your question.

Might I suggest moving to either:
a) one of our 107-L probes, or
b) using a CR800 or CR1000 datalogger?

Hope this sparks some ideas:

Manual:
http://www.waterlog.com/Downloads/manuals/Current%20Manuals/Entire%20H-377%20Manual.pdf

Temperature of thermistor:
T = 1/(a + b(Ln Rt) + c(Ln Rt)^3)

SHH Coefficients:
a=0.0010291636, b=0.0002391251 c=0.0000001566

Resistance of reference resistor (note using 2500mV excitation):
Rt=20000 * ((2500 / mV) - 1)

--

;{CR10X}
;
*Table 1 Program
01: 10.0000 Execution Interval (seconds)

1: Excite-Delay (SE) (P4)
1: 1 Reps
2: 5 2500 mV Slow Range
3: 1 SE Channel
4: 1 Excite all reps w/Exchan 1
5: 100 Delay (0.01 sec units)
6: 2500 mV Excitation
7: 2 Loc [ RT_V ]
8: .001 Multiplier
9: 0.0 Offset

2: Z=1/X (P42)
1: 2 X Loc [ RT_V ]
2: 1 Z Loc [ RT ]

3: Z=X*F (P37)
1: 1 X Loc [ RT ]
2: 50000 F
3: 1 Z Loc [ RT ]

4: Z=X+F (P34)
1: 1 X Loc [ RT ]
2: -20000 F
3: 1 Z Loc [ RT ]


;Note the error your going to get because of the
;misrepresentation of the coefficients
5: Steinhart-Hart Equation (P200)
1: 1 Reps
2: 1 Source Loc (R)(Ohms) [ RT ]
3: 3 Destination Loc (Deg C) [ T ]
4: 10291 A
5: -7 x 10^n
6: 23912 B
7: -8 x 10^n
8: 1566 C
9: -10 x 10^n


*Table 2 Program
02: 0.0000 Execution Interval (seconds)

*Table 3 Subroutines

End Program


skimball Nov 30, 2011 03:22 PM

What would the program look like for a CR1000? How would it be wired?


Dizbert Nov 30, 2011 09:32 PM

Hey Guys,

I'll give it a shot.

Code for a CR1000:

BrHalf (V1_Vx,1,mV2500,1,Vx1,1,2500,True ,0,250,1.0,0)

Rt=20000*(V1_Vx/(1-V1_Vx))

H377_temp =1/(0.0010291636+(0.0002391251*(LN(Rt)))+(0.0000001566*(LN(Rt))^3))

or for a CR10X:

1: AC Half Bridge (P5)
1: 1 Reps
2: 25 2500 mV 60 Hz Rejection Range
3: 1 SE Channel
4: 1 Excite all reps w/Exchan 1
5: 2500 mV Excitation
6: 1 Loc [ V1_Vx ]
7: 1.0 Multiplier
8: 0.0 Offset

2: BR Transform Rf[X/(1-X)] (P59)
1: 1 Reps
2: 1 Loc [ V1_Vx ]
3: 20000 Multiplier (Rf)

3: Steinhart-Hart Equation (P200)
1: 1 Reps
2: 1 Source Loc (R)(Ohms) [ V1_Vx ]
3: 2 Destination Loc (Deg C) [ H377_temp ]
4: 10291 A
5: -07 x 10^n
6: 23912 B
7: -08 x 10^n
8: 1566 C
9: -10 x 10^n

As for wiring it looks like Red goes to Excitation #1, White to SE #1, and Black to Analog Ground. If your not sure, use a ohm meter to check that you have 20000 ohms between the two wire connecting se and excitation, and greater than 20000 between the two wires connecting excitation and ground.

* Last updated by: Dizbert on 12/1/2011 @ 11:36 AM *


Dizbert Nov 30, 2011 09:33 PM

Sorry second post by mistake.

* Last updated by: Dizbert on 11/30/2011 @ 2:37 PM *

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