User manual

Page 55
EA Elektro-Automatik GmbH
Helmholtzstr. 31-33 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
[e-mail]
PSI 9000 DT Series
3.5.4 Remote control via the analog interface (AI)
3.5.4.1 General
The built-in, up to 1500 V DC galvanically isolated 15-pole analog interface (short: AI) is on the rear side of the
device offers the following possibilities:
• Remote control of current, voltage, power and internal resistance
• Remote status monitoring (CC/CP, CV)
• Remote alarm monitoring (OT, OVP, PF)
• Remote monitoring of actual values
• Remote on/off switching of the DC output
Setting the three set values of voltage, current and power via the analog interface always takes place concurrently.
It means, that for example the voltage can’t be given via the AI and current and power set by the rotary knobs, or
vice versa. The internal resistance set value can addtionally be adjusted.
The OVP set value and other supervision (events) and alarm thresholds cannot be set via the AI and therefore
must be adapted to the given situation before the AI is put in operation. Analog set values can be fed in by an ex-
ternal voltage or generated by the reference voltage on pin 3. As soon as remote control via the analog interface
is activated, the values displayed will be those provided by the interface.
The AI can be operated in the common voltage ranges 0...5 V and 0...10 V in each case 0...100% of the nominal
value. The selection of the voltage range can be done in the device setup. See section „3.4.3. Conguration via
MENU“ for details.
The reference voltage sent out from Pin 3 (VREF) will be adapted accordingly and is then:
0-5 V: Reference voltage = 5 V, 0...5 V set values (VSEL, CSEL, PSEL, RSEL) correspond to 0...100% nominal
values, 0...100% actual values correspond to 0...5 V at the actual value outputs (CMON, VMON).
0-10 V: .Reference voltage = 10 V, 0...10 V set values (VSEL, CSEL, PSEL RSEL) correspond to 0...100% nominal
values, 0...100% actual values correspond to 0...10 V at the actual value outputs (CMON, VMON).
Input of excess set values (e.g. >5 V in selected 5 V range or >10 V in the 10 V range) are clipped by setting the
set value at 100%.
Before you begin, please read. Important notes for use of the interface:
• Analogremotecontrolofthedevicemustbeactivatedbyswitchingpin“REMOTE”(5)rst.Onlyexceptionis
pinREM-SB,whichcanbeusedindependentlysinceKErmwareversion2.07
• Before the hardware is connected that will control the analog interface, it shall be checked that it can’t provide
voltagetothepinshigherthanspecied
• Set value inputs, such as VSEL, CSEL, PSEL and RSEL (if R mode is activated), must not be left unconnected
(i.e.oating)
• It is always required to provide all three set values at once. In case any of the set values is not used for adjust-
ment,itcanbetiedtoadenedlevelorconnectedtopinVREF(solderbridgeordifferent),soitgives100%
The analog interface is galvanically separated from DC output. Therefore do not connect any
ground of the analog interface to the DC- or DC+ output!
3.5.4.2 Resolution and sample rate
The analog interface is internally sampled and processed by a digital microcontroller. This causes a limited resolu-
tion of analog steps. The resolution is the same for set values (VSEL etc.) and actual values (VMON/CMON) and
is 26214. Due to tolerances, the truly achievable resolution can be slightly lower.
There is furthermore a max. sample rate of 500 Hz. It means, the device can acquire analog set values and sta-
tuses on digital pins 500 times per second. The same applies for generated output signals, such as monitor values.