Ea Elektro Automatik EA Elektro-Automatik EA-ELR 9250-140 3U Electronic Load 0 - 140 A 0 - 250 Vdc 0 - 7000 W 33200406 データシート

Page 58

EA Elektro-Automatik GmbH

Helmholtzstr. 31-33 • 41747 Viersen

Germany

Fon: +49 2162 / 3785-0

Fax: +49 2162 / 16230

The built-in function generator is able to create various signal forms and apply these to the set value of voltage 

or current.
In manual operation, all generator functions are available for access on the front panel. In remote control, only the 

customisable arbitrary generator and a XY function are available. The arbitrary generator can replicate all manually 

serviceable functions, except UI and IU. For those, the XY function is assigned.
The following functions are retrievable, configurable and controllable:

Sine wave

U, I

Sine wave generation with adjustable amplitude, offset and frequency

Triangle

U, I

Triangular wave signal generation with adjustable amplitude, offset, gain and decay times 

Rectangular U, I

Rectangular wave signal generation with adjustable amplitude, offset and duty cycle

Trapezoid

U, I

Trapezoidal wave signal generation with adjustable amplitude, offset, rise time, pulse 

time, fall time, idle time

DIN 40839

-

Simulated automobile engine start curve according to DIN 40839 / EN ISO 7637, split 

into 5 curve sequences, each with a start voltage, final voltage and time

Arbitrary

U, I

Generation of a process with up to 100 freely configurable steps, each with a start and 

end value (AC/DC), start and end frequency, phase angle and total duration

Ramp

U, I

Generation of a linear rise or fall ramp with start and end values and time before and 

after the ramp

UI-IU

-

Table (.csv) with values for U or I, uploaded from a USB flash drive

3.9.2.1  Limitations
The function generator is not accessible, neither for manual access, nor for remote control, if
•

master-slave mode has been activated and the device was configured as slave.

•

resistance modes (R/I adjustment mode, also called UIR mode) is active.

3.9.2.2  Resolution of X (time) and Y (amplitude)
The function generator can set 4096 steps between 0 ... 100% of any nominal value. The intervals to create a 

linear or other rise/fall are calculated depending on the amplitude and then set.
If the amplitude is very low and the time long, only few intervals will be set as otherwise many identical values will 

be set one after another, generating a staircase effect.

In order to understand how the function generator works and how the value settings interact, the following should 

be noted: 
The device operates always with the three set values U,I and P, also in function generator mode. 
The selected function can be used on one of the values U or I, the other two are then constants and have a limit-

ing effect. That means, if, e.g. a voltage of 10 V is applied to the DC input and a sine wave function should oper-

ate on the current with an amplitude of 20 A and offset 20 A, then the function generator will create a sine wave 

progression of current between 0 A (min) and 40 A (max), which will result in an input power between 0 W (min) 

and 400 W (max).The input power, however, is limited to its set value. If this were 300 W then, in this case, the 

current would be limited to 30 A and, if clamped to an oscilloscope, it would be seen to be capped at 30 A and 

never achieve the target of 40 A.
Another case is when working with a function which is applied to the input voltage. If here the static voltage is 

set higher than the amplitude plus offset then at function start there will be no reaction, as the voltage regulation 

limits down to 0 with an electronic load, other than current or power. The correct settings for each of the other set 

values is therefore essential.