SECTION 7. MEASUREMENT PROGRAMMING EXAMPLES

FIGURE 7.3-1. CR10TCR Mounted on the CR10 Wiring Panel
7.3 THERMOCOUPLE TEMPERATURES

 

 

PROGRAM

USING THE OPTIONAL CR10TCR TO

01:

P11

Temp 107 Probe

MEASURE THE REFERENCE

01:

1

Rep

TEMPERATURE

02:

1

IN Chan

The CR10TCR Thermocouple Reference is a

03:

3

Excite all reps w/EXchan 3

04:

1

Loc [:REF TEMP ]

temperature reference for thermocouples

05:

1

Mult

measured with the CR10 Measurement and

06:

0

Offset

Control Module. When installed, the CR10TCR

02:

P14

Thermocouple Temp (DIFF)

lies between the two analog input terminal

01:

5

Reps

strips of the CR10 Wiring Panel (see Figure

02:

22

7.5 mV 60 Hz rejection Range

7.3-1). The CR10TCR circuitry, measurement,

 

 

 

and specifications are equivalent to Campbell

03:

2

IN Chan

Scientific's 107 Temperature Probe.

04:

1

Type T (Copper-Constantan)

The CR10TCR is connected to single-ended

05:

1

Ref Temp Loc REF TEMP

channel 1 (1H), excitation channel 3 (E3) and

06:

2

Loc [:TC #1 ]

analog ground (AG). It is measured with

07:

1

Mult

Instruction 11 which excites the probe with a

08:

0

Offset

2.5VAC excitation, makes a single ended

 

 

 

measurement and calculates temperature (°C).

7.4 THERMOCOUPLE TEMPERATURES

Five differential thermocouples are measured

USING AN EXTERNAL REFERENCE

with Instruction 14. (Refer to the CR10TCR

JUNCTION

 

Manual for instructions on measuring a

 

thermocouple in differential channel 1.)

When a number of thermocouple measurements

The temperature (°C) of the CR10TCR is stored

are made at some distance from the CR10, it is

in Input Location 1 and the thermocouple

often better to use a reference junction box

located at the site rather than use the CR10TCR

temperatures (°C) in Locations 2-6.

Thermocouple Reference. Use of the external

 

 

reference junction reduces the required length of

 

expensive thermocouple wire as regular copper

 

wire can be used between the junction box (J-box)

 

and CR10. In addition, if the temperature gradient

 

between the J-box and the thermocouple

 

measurement junction is smaller than the gradient

 

between the CR10 and the measurement junction,

 

thermocouple accuracy is improved.

7-3