Heinzinger electronic GmbH
Phone: +49 (0) 8031 2458 0
www.heinzinger.com
Anton-Jakob-Str. 4, 83026 Rosenheim
Fax: + 49 (0) 8031 2458 58
Germany
Page 113
ERS COMPACT
4.3
Calibration
4.3.1
Preface
The devices of series ERSC 10000 don’t have a built- in feature to re-adjust the most important DC terminal re
-
lated values, but they can still be readjusted using the software
EA Power Control. The required calibration app
is included in the free of charge base version of this software. In order to use the feature is may be necessary to
install a n update of this software.
Re-adjustment is intended to compensate small deviations of the output related values of voltage and current in a
range of up to 1% or 2% of the rated value. There are several reasons which could make it necessary to re-adjust
a unit: component aging, component deterioration, extreme ambient conditions, high frequent use.
In order to determine if a value is out of tolerance, the parameter must first be verified with measurement tools
of high accuracy and with at least half the error of the ERSC device. Only then a comparison between values
displayed on the ERSC device and true DC output/input values is possible.
For example, if you want to verify and possibly readjust the output current of model ERSC 10080-1000 4U which
has 1000 A maximum current stated with an accuracy of
<
0.1% you can only do that by using a high current shunt
or current transducer with max. 0.05% or less error. Also, when measuring such high currents, it’s recommended
to keep the process short, in order to avoid the shunt heating up too much. It’s furthermore recommended to use
a shunt with at least 25% reserve.
When measuring the current with a shunt, the measurement error of the multimeter on the shunt adds to the error
of the shunt and the sum of both must not exceed the max. error of the device under calibration.
4.3.2
Preparation
For a successful calibration and readjustment, a few tools and certain ambient conditions are required:
•
A measurement device (multimeter) for voltage, with a max. error of half the ERSC’s voltage error. That mea
-
surement device can also be used to measure the shunt voltage when readjusting the current
•
If the current is also going to be calibrated: a suitable DC current shunt or transducer, ideally specified for at least
1.25 times the max. current rating of the ERSC and with a max. error that is half or less than the max. current
error of the ERSC device to calibrate
•
Normal ambient temperature of approx. 20-25°C
•
One or two adjustable loads, preferably electronic ones, which are capable of consuming at least 102% of the
max. voltage and current of the ERSC device and which are calibrated and precise
•
An adjustable source which is capable of supplying at least 102% of the max. voltage and current of the ERSC
device and which is calibrated and precise
Before you can start calibrating, a few measures have to be taken:
•
Let the ERSC device warm up for at least 10 minutes under 50% load, in connection with the voltage / current
source
•
In case the remote sensing input is going to be calibrated, prepare a cable for the remote sensing connector to
the DC terminal, but leave it yet unconnected
•
Abort any form of remote control, deactivate master-slave mode, deactivate resistance mode
•
Install the shunt or transducer between the ERSC device and the load/source and make sure the shunt/trans
-
ducer is cooled somehow
•
Connect external measurement devices to the DC terminal and/or to the shunt/transducer, depending on whether
the voltage is going to be calibrated first or the current
4.3.3
Calibration procedure
The re-adjustment is done in the graphical user interface of EA Power Control. The software will guide through
the process with instructions, as far as possible. The user manual of the software holds additional information.