IOtech MultiScan 1200, Руководство пользователя

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TempScan / MultiScan User's Manual Chapter 8: ChartView & ChartView Plus 87
Channel Configuration Columns
1.
Channel (CH)

This column serves only as a channel number indicator. The channel number
cannot be changed from this column.
2.
On 
The On column allows you to enable a channel for data collection. When a cell or block of
cells in this column is selected, a selection box will appear that allows “On” to enable or “Off” to
disable the channel. Double-clicking a cell in this column toggles the channel’s enable status.
Clicking the
Make All Channels Active button enables (turns all channels “on”). Clicking on the
Make All Channels Inactive button disables all channels (turns them “off”), with the exception
that channels assigned to charts can only be turned off from the display configuration setup.
3.
Readings

The reading column displays the scanning device input readings. The column is
activated when you select the Enable SpreadSheet Reading button. The column’s values are real-
time channel values from the instrument and cannot be altered by the user. This column will
update the readings as fast as the computer will allow.
Note: Other areas of the SpreadSheet cannot be altered while the channel Readings column is
enabled.
4.
Type
 A block of cells in this column can be selected for convenience of single type selection.
Double-clicking a cell will select the next available type.
5.
Label

The Label column identifies the input channel by descriptive name. The label is used
when selecting a channel in the trigger and chart selection lists. The label column automatically
uses the channel number as a default. You can change the label to any alpha-numeric designation
not exceeding eight characters. Each label used must be unique (specific) to its designated
channel.
6.
Units

Cells in the Units column are dependent on the Type selected and automatically change
when the type is changed, for example temperature units will be replaced by volts units when
changing from a thermocouple type to a volts type.
If the channel is configured for Temperature the units automatically change to ° C (default); at
this point, you have the option of selecting a different engineering temperature unit (
°
F,
°
K,
°
R).
Note that the mX+b equation, discussed in the following text, is typically not used for
temperature readings, since temperature data will be linear. However, you can use the
equation in temperature applications, for example: setting b to -32 in order to watch deviations
from freezing point when temperature is in °F.
In addition, with ChartView Plus you can subtract a reference channel from the mX+b equation to
obtain a temperature differential, as indicated in the following example.
Example:
A heated room has 2 thermocouples (T1 for CH1 and T2 for CH2); with T1 being in the center of
the room and T2 positioned at an outer wall. If the outer wall is monitored to ensure a temperature
within ±2°F (of the temperature indicated by thermocouple T1), then CH1 can be used as a
reference channel such that its value will be subtracted from the actual value for channel 2.
Assume the central thermocouple is reading 90.5°F and the outer thermocouple (for CH2) is
reading 89.0°F. In this case we can use the equation so channel 2’s charted reading will not be of
the actual temperature, but will be the differential between CH1 and CH2, e.g.:
y = (mX + b) - ref. chan
; where:
y = Channel 2’s charted value (a temperature
differential)
m = 1
b = 0
X = CH2
ref. Chan. = CH1
Channel 2’s charted value = (1 x CH2 + 0) - CH1
Channel 2’s charted value = (1 x 89.0°F + 0) - 90.5°F
Channel 2’s charted value = -1.5°F
Note: The reference channel feature is only available with ChartView Plus .