7.2 Measuring Point Scans
(see also manual 6.5.)
Meas. point scans can be used to acquire, indicate and, in most cases, to
document data from the selected meas. point and also from (up to 4) other
channels.
When a meas. point scan is performed the meas.inputs of the active meas.
points will, at the conversion rate, be switched to the measuring circuit, the
measured values will be acquired and provided as output to the connected
peripheral device (s. 8.). Max and min values will be updated, exceeding of
limit values will be monitored and average values will, possibly, be calculated.
With the switchboard instrument ALMEMO
®
4490-2 the programming and
triggering of measuring point scans is, generally, only performed via the
interface (s. man. 6.6.1). Only
continuous measuring point scans
without an
output can be set via the function conversion rate ´
CR
´ (see 7.1.2).
However, if the corresponding programming is available, the measuring point
scans can also be started and stopped via exceeding of limit values (s. man.
6.6.3) or via trigger cable (s. man. 6.6.4). As long as no cycle has been
programmed
single measuring point scans
will be performed. For
cyclic
measuring point scans
the print cycle or measuring cycle (s. man. 6.5.2/3)
must be programmed. Depending on the application the output format can be
selected as list format, column format or spreadsheet (table) format (s. man.
6.5.5). All parameters will also be maintained after a switch off.
8. ANALOGUE OUTPUT
The following three options are available for an analogue registration of the
selected measuring point:
1. Connection of an analogue output cable ZA 1601-RK (-1.25V to 2.0V)
without electrical isolation (s. man. 5.1.1).
2. Connection of a relay trigger analogue adapter ZA 8000-RTA with electrically
isolated analogue output to the sockets A1 or A2 (s. man. 5.1.3).
3. Use of an integrated, electrically isolated analogue output, which is available
as option Rx.
Option
Output Signal
Slope (Gain)
OA 4490-R1
-1.2500 V ... +2.0000 V
0.1 mV/digit
OA 4490-R2
-6.0000 V ... +10.0000 V
0.5 mV/digit
OA 4490-R3
0.000 mA ... +20.000 mA
1 µA/digit
The connection of a recording device can be performed via a terminal screw
connector and the terminals Out + and - ( 7 ).
The analogue output value corresponds to the linearized measured value. For
the measuring range 55 mV the specified slope (gain) refers to 2 digits. In case
of a sensor breakage the output voltage will turn to zero.
30
ALMEMO
4490-2
Digital Data Output
