14
GOSSEN METRAWATT GMBH
8.2
Read-Out a Periodic Ramp – RAMP Function
Ramp-type signals can be used to test dynamic performance
of devices under test, or entire measuring circuits. An exam-
ple would be control loop performance with a setpoint speci-
fied via the analog setpoint input at the controller. The instru-
ment can be used to replace costly hardware and software
for the set-up of long-term test bays with cyclical time
sequences.
Parameters for the ramps depicted below include:
•
The following functions can be adjusted as output quanti-
ties:
voltage U, current sink I Sink, current source I Source,
resistance R or temperature temp.
•
A lower (
Start
) and an upper (
End
) range limit can be
selected for each output quantity. For standard signals
these are always 0
…
10 V and 0/4
…
20 mA, and are
otherwise values from within the entire range.
•
Rise time t1 and decline time t3 are
adjustable from 0 seconds
…
60 minutes.
•
Dwell time t2 at the upper and lower range limits is
adjustable from 0 seconds
…
60 minutes.
•
There are 2 ramp sequences:
– Once only: t1, t2, t3
– Repetitive: t1, t2, t3, t2, t1, t2, t3,
…
Examples of Ramp Sequences:
Example of a Periodic Ramp Sequence
Manually Controlled Ramp Sequences
After configuring all parameters in accordance with the menu
flowchart on page 15, rising or declining ramps can be trig-
gered with the
"
and
the
#
keys.
The relationship between the output signal and each of the
key operations is depicted with the help of the following
example.
Example of a Manually Controlled Ramp Sequence
Ramp parameters: Output quantity: U (0
…
15 V range),
Start
= 2 V,
End
= 10 V, t1 = 5 s, t2 = 8 s, t3 = 5 s,
repeat = Yes (yes for periodic ramp)
Key
1 The sequence is started by pressing the
↵
key when
ramp
start
is displayed (see Menu Flowchart on page 16).
2 Stop the declining ramp within decline time t3 with the
"
or
the
#
key.
3 Start a rising ramp within remaining decline time t3 with
the
"
key.
4 Stop the ramp sequence with the
"
or
the
#
key.
5 Start a declining ramp with the
#
key, remaining dwell
time t2 is deleted.
6 Stop the ramp sequence by simultaneously pressing and
holding the
"
and
the
#
keys (2 audible acoustic signals
must be generated).
Start
End
t1
t2
t3
t2
Output
t
2 V
10 V
t1
t2
t3
LCD:
t3
t2
t1
➀
➁
➂
➃ ➄
➅
t1 up
t2 run
t3 dn t3 hld t3 up t3 run t3 hld t1 dn
stop
cont.
stop cont.
U [V]
+
"
#
#"
#
"
#"