VTI Instruments EX1000A, Руководство пользователя

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EX10xxA Triggering 59
The measurement range of the EX10xxA in terms of temperature is a function of its input voltage
range and the capabilities of the thermocouple sensors themselves. Specifically, the measurement
range of the EX10xxA for the standard thermocouple types is the following:
Type Min (°C) Max (°C) Min (°F) Max (°F)
J -200 1200 -328 2192
K -200 1372 -328 2502
T -200 400 -328 752
E -200 900 -328 1652
S -50 1768 -58 3214
R -50 1768 -58 3214
B 250 1820 482 3308
N -200 1300 -328 2372
T
ABLE
3-2: EX10
XX
A M
EASUREMENT
R
ANGE
In addition to the standard thermocouple types, the EX10xxA can accept and measure a custom
thermocouple of any type. The effective measurement range in temperature is subsequently
determined by the input voltage range of the EX10xxA and the thermocouple transfer function of
the custom thermocouple.
In terms of voltage, the thermocouple connectors may only accept an input voltage of ±67 mV when
performing temperature conversion. When in voltage mode, these connectors can accept either
±0.067 V or ±0.1 V inputs. The voltage connectors may use either ±0.01 V, ±0.067 V, ±0.1 V,
±1.0 V, or ±10.0 V inputs for both EU temperature conversion or voltage measurements. When
temperature is selected, the instrument automatically switches the selected channel(s) to the ±67 mV
range. The EX1000A-TC is a special case where thermocouple inputs are used for voltage
measurement and may utilize all input ranges available to the voltage connectors. Table 1- provides
an overview of each models capabilities.
C
OLD
J
UNCTION
C
OMPENSATION
(CJC)
For highest accuracy and stability, the EX1000A-TC, EX1016A, EX1032A, EX1048A and RX1032
provide embedded isothermal input sections that are monitored by twelve precision thermistors
(based on Model#, number of thermistors may vary), one for every four thermocouple channels.
(Note, the EX1000A may utilize external thermistors as described in the
Voltage Connections
section). To ensure that CJC information is current and time correlated with the input channels, CJC
channels are measured with every scan, providing a maximum time separation of less than 4 ms
between the input channel measurement and its associated CJC measurement. Table 3-3 shows the
association between the CJC and input channels.
CJC # Channel Input Channel
CJC0 48 0-3
CJC1 49 4-7
CJC2 50 8-11
CJC3 51 12-15
CJC4 52 16-19
CJC5 53 20-23
CJC6 54 24-27
CJC7 55 28-31
CJC8 56 32-35
CJC9 57 36-39
CJC10 58 40-43
CJC11 59 44-47
T
ABLE
3-3: CJC C
HANNEL
/ I
NPUT
C
HANNEL
R
ELATIONSHIP