User Manual
Page 93
EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
ea1974@elektroautomatik.de
PSB 9000 2.5 kW Series
4.3 Calibration
4.3.1 Preface
The devices of series PSB 9000 don’t have a built- in feature to re-adjust the most important DC terminal related
values, but they can still be readjusted using the software EA Power Control. The required calibration app is in-
cluded 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.
Inordertodetermineifavalueisoutoftolerance,theparametermustrstbeveriedwithmeasurementtoolsof
high accuracy and with at least half the error of the PSB device. Only then a comparison between values displayed
on the PSB device and the true value on the DC terminal is possible.
For example, if you want to verify and possibly readjust the output current of model PSB 9080-120 which has
120 A maximum current, stated with a max. error of 0.2%, you can only do that by using a high current shunt or
current transducer with max. 0.1% error or less. 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 PSB’s voltage error. That measure-
ment device can also be used to measure the shunt voltage when readjusting the current
• Ifthecurrentisalsogoingtobecalibrated:asuitableDCcurrentshuntortransducer,ideallyspeciedforat
least 1.25 times the max. current rating of the PSB and with a max. error that is half or less than the max. current
error of the PSB 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 PSI 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 PSB
device and which is calibrated and precise
Before you can start calibrating, a few measures have to be taken:
• Let the PSB 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 PSB device and the load/source and make sure the shunt/transducer
is cooled somehow
• Connect external measurement devices to the DC terminal and/or to the shunt/transducer, depending on whether
thevoltageisgoingtobecalibratedrstorthecurrent
4.3.3 Calibration procedure
The re-adjustment is done in the graphical user interface of EA Power Control version 2.15 or newer. The soft-
ware will guide through the process with instructions, as far as possible. The user manual of the software holds
additional information.