Page 82
EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
PSB 9000 3U Series
Schematic diagram:
Application and result:
A
.st
ar
t
t
A
t1
t2
A
.E
nd
This function generates a rising or falling ramp between start and end
values over the time t2. Time t1 creates a delay before the ramp starts.
The function runs once and stops at the end value. To have a re-
peating ramp, function Trapezoid would have to be used instead
Important to consider are the static values of U and I which define
the start levels at the beginning of the ramp. It is recommended that
these values are set equal to those in A.start (parameters Ustart or
Istart), unless the load at the DC output in source mode should not
be provided with voltage before the start of the ramp or the external
source not be loaded with current yet in sink mode. In that case the
static value should be set to zero.
3.11.12 Battery test function
This function only works in sink mode.
The purpose of the battery test function is to discharge various battery types
in industrial product tests or laboratory applications. It is only available via
access on the HMI, at least regarding setup and use as described below, but
can also be achieved in remote control using the arbitrary function generator.
The only disadvantage in remote control are the missing counters of battery
capacity (Ah), energy (Wh) and time. But those can be calculated by custom
remote control software when programming a time counter and regularly
querying actual values from the device.
The function is usually applied to the DC input current in sink mode and can either be selected and run in
“Static”
(constant current)
or
“Dynamic” (pulsed current)
mode. In static mode, the settings for power or resistance
can also let the device run the function in constant power (CP) or constant resistance (CR). Like with the normal
operation of the device the set values determine what regulation mode (CC, CP, CR) is active. If, for example, CP
operation is projected, the set values of current should be set to maximum and resistance mode should be turned
off, so that both don’t interfere. For a projected CR operation it is similar. There current and power should be set
to maximum.
For dynamic mode there is also a power setting, but it cannot be used to run the dynamic battery test function in
pulsed power mode or at least the result would not be as expected. It is recommended to adjust the power values
always according to the test parameters, so it doesn’t interfere with the pulsed current, i. e. dynamic mode.
When discharging with high currents, compared to the nominal battery capacity and in dynamic mode, it may hap-
pen that the battery voltage shortly drops below the U-DV threshold and the test will unintentionally stop. Here it
is recommended to adjust U-DV accordingly.
Graphical depiction of both battery test modes:
U, I
t
Discharge current
Start
U-DV
Stop
U, I
t
Discharge current
Start
U-DV
Stop
Static
Dynamic
