User manual

Page 28
EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
[e-mail]
EL 9000 B HP Series
2.3.5 Grounding of the DC input
The device can always be grounded on the DC minus pole, i.e. can be directly connected to PE. The DC plus pole,
however, if it is to be grounded, may only be so for input voltages up to 400 V, because the potential of the minus
poleisshiftedintonegativedirectionbythevalueoftheinputvoltage.Alsoseetechnicalspecicationsheetsin
1.8.3, item “Insulation”.
For this reason, for all models which can support an input voltage higher than 400 V grounding of the DC plus
pole is not allowed.
• Do not ground the DC plus pole on any model with >400 V nominal voltage
• If grounding one of the input poles ensure that no output pole of the source (e.g. power supply)
is grounded. This could lead to a short-circuit!
2.3.6 Connecting the “Share” bus
The “Share” bus connector on the back side is intended to balance the current of multiple units in parallel opera-
tion, especially when using the integrated function generator of the master unit. Alternatively, it can be connected
to a compatible power supply, like from series PSI 9000 3U, in order to run a two-quadrants operation. For further
information about this mode of operation can be found in section „3.11.3. Two quadrants operation (2QO)“ .
For the connection of the share bus the following must be paid attention to:
• Connection is only permitted between up to 10 units and only between compatible devices
as listed in section „1.9.9. “Share” connector“
• If a two-quadrants operation system has to be set up where multiple power supplies are
connected to one electronic load unit or a group of electronic loads, all units should be
connected via Share bus.
2.3.7 Connection of remote sensing
• Both pins “NC” on the “Sense” terminal must not be connected!
• This series features models with up to 750 V DC rated voltage, so it is required to only use
remote sensing leads with proper electric strength
• Remote sensing is only effective during constant voltage operation (CV) and for other regulation
modes the sense input should be disconnected, if possible, because connecting it generally
increases the oscillation tendency.
• The cross section of the sensing cables is noncritical. Recommendation for cables up to 5 m:
use at least 0.75 mm²
• Sensing cables should be twisted and laid close to the DC cables to damp oscillation. If neces-
sary, an additional capacitor should be installed at the source to eliminate oscillation
• Sensing cables must be connected + to + and - to - at the source, otherwise the sense input
of the electronic load can be damaged. For an example see Figure 7 below.
• In master-slave operation, the remote sensing should be connected to the master unit only
Figure 7 - Principle of remote sensing wiring
2.3.8 Connecting the USB port (rear side)
In order to remotely control the device via this port, connect the device with a PC using the included USB cable