Fluke 1586A, Руководство пользователя

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Input and Channel Configuration
Mx+B, Alarms, and Channel Options
3
3-31
The Product uses the offset to zero a channel. To do this, the Product calculates the offset
required to convert the measurement to a zero value, sets Mx+B to ON, and loads the
calculated offset value into the Mx+B settings. To clear the zero, the offset value can be
manually set back to the original value (usually “0”) or Mx+B can be set to OFF if it was
off before the channel was zeroed. See “Zero a Channel” on page 3-14 for instructions on
how to zero a channel.
To apply an Mx+B scaling to a channel:
1. Push

.
2. Push

or

to highlight a channel.
3. Set the channel to ON if necessary.
4. Push

to edit the channel.
5. Select Mx+B and push

.
6. Input the Gain and Offset values and set the unit as desired. When complete, push

to return to the previous menu.
7. Verify the channel. If the scaled channel gives unexpected results (like zero or
“OL”):
•
Verify that the correct gain and offset values are set.
•
Manually calculate the result with the entered gain and offset values. See the
examples in this section.
•
Temporarily set the gain to 1 and the offset to 0 to verify that the measurements
are in the expected range. Unexpected measurements could result from a wiring
error or the wrong range or function selected.
HI and LO Channel Alarms
Each channel has two channel alarms that can have custom values assigned to trip when a
channel measurement exceeds the assigned high (HI) or low (LO) limit. If an alarm trips,
the measurement value on the display changes to red and will stay red until the
measurement is back in the normal range.
In addition to the visual indication, the channel alarm can be tied to one of the six alarm
outputs on the rear panel (see Figure 3-10 and Figure 3-11). An alarm output can have
multiple channels assigned to it. If an alarm trips, the alarm outputs a low condition
signal (<0.7 V dc). A common use of this feature is to connect to an external audio alarm
that will sound if the channel alarm is tripped.
To set a channel alarm:
1. Push

.
2. Push

or

to highlight a channel then push

.
3. Push

or

to highlight Alarm then push

.
4. Select Alarm 1 or Alarm 2 then push

.