Martel Electronics MasterCAL - Manual (Page 75)

Calibrator
Using Source Mode
65
Ramping the Output
Ramping sweeps the source up or down in value.
Use the ramp feature to check a limit switch or
alarm, or any time you want a smoothly increasing or
decreasing output function. You can set the
calibrator to ramp up or down in engineering units
(mV, V, mA, °C, etc.) or % of scale.
During ramping, the output is adjusted 4 times per
second. The size of the steps is determined by your
choices of endpoints and ramp time. For example, if
you set the calibrator to ramp from 1 mV to 1 V over
10 seconds, the output is adjusted in approximately
25 mV steps.
Ramping continues until the selected limit is
reached, or until an optional trip condition is
encountered. The optional trip detect works as
follows: during ramping, the calibrator checks for
either a 1 V change in dc voltage or a change in
continuity status (
Open or Short ) from one ¼ second
interval to the next.
Proceed as follows to ramp (i.e., sweep the source):
1. Refer to the appropriate heading earlier in this
manual (e.g., “Sourcing Electrical Parameters”)
and connect the calibrator to the circuit to be
tested. Figure 22 shows an example.
2. To automatically stop ramping if a trip condition
is detected, connect a voltage trip circuit to the V
MEAS jacks or a continuity trip circuit to the mA
Ω
RTD MEAS jacks. (Continuity detection is not
available when sourcing current.)
3. If necessary, press M for SOURCE mode.
4. Set the calibrator for the desired source value as
previously described.
5. If you want to ramp the output in % of scale, set
% of scale as described previously under
“Sourcing in Percent of Scale.”
6. Press the More Choices softkey.