Technical data

6
©
FuG Elektronik GmbH, D-83135 Schechen, Am Eschengrund 11
http://www.fug-elektronik.de, E-Mail: [e-mail]
V 0913
Low voltage power supplies double stabilized
Series NTN from 6,5 V to 350 V / 35 W to 100 kW
NTN 700 - 125
125V / 5A
Design Example
Features:
 Simple construction
 Short circuit proof and unlim-
ited operation with full current
in short circuit condition
 Voltage and current regulation
with automatic and sharp
transition; control modes
indicated by LEDs
 Voltage and current setting
via 10-turn potentiometers
with precision scale; the ad-
justing knob can be locked
 4½ digit DVM for voltage and
current (for table-top models)
 Sense terminals for the com-
pensation of voltage drop on
the load lines. The nominal
voltage always refers to the
output terminals
 Parallel and series connection
possible
 Suitable also for inductive and
capacitive loads
 Safety interlock loop and
internal interlock is standard
on three-phase units
 Elapsed-hour meter as a
standard on three-phase units
Function:
The mains voltage is transfor-
med to the appropriate level. On
the secondary side of the trans-
former is a thyristor controlled
rectifier stage (phase cutting
circuit), the output of which is
used to charge a capacitor
bank. This capacitor bank is
also connected to the final se-
ries regulating transistor output
stage. By controlling the con-
duction angle of the thyristors
after each zero-crossing of the
sinusoidal voltage, the flow of
energy is regulated in such a
way as to have a defined volt-
age drop across the final series
transistor stage (pre-regulation).
The performance of the final
series transistor stage defines
the final stability of the output
voltage (main regulation).
Design:
 Up to 140W nominal power
½19" table-top case
 For 350W nominal power or
higher 19" table-top case
 19" Rack-adapters for mount-
ing into a 19" rack are availa-
ble as accessory
 For 7kW nominal power or
higher 19" cabinet. Height
depending on type. The side
covers are detachable and the
rear door is lockable.
 All cabinets are equipped with
fork-lift-compatible plinths and
removable crane-eyes.
 Single cabinets up to 38U are
easily transportable by fork-
lift.
 Cooling is carried out via
convection or built-in fans,
with the air being exhausted
(depending upon type) either
via the rear or the top. For
high power units water cool-
ing can also be used.
Output:
 Output isolation:
The output is floating, maxi-
mum operating voltage with
respect to earth: ±500V. Ei-
ther the positive or the nega-
tive terminal may be connect-
ed to earth. For units
equipped with the analog
programming: the "0V" of the
analog programming is con-
nected to the positive output.
 Output terminals:
Up to 20A output current,
4mm safety connectors are
used on the rear side. For
currents up to 300A - clamps
are fitted whilst for higher
currents we use copper bars.
Technical Data:
 Mains connection:
Up to 1400W nominal power:
230V ±10% 47Hz to 53Hz
For 2800W and higher:
400V ±10% 47Hz to 53Hz;
two-phase
For 7000W and higher:
400V ±10% 47Hz to 53Hz;
three-phase
 Ambient temperature: 0°C to
+40°C
The following data applies for
voltage and current regulation,
and refers to the rated value
(unless otherwise stated):
(For explanations please refer
to Definitions and Terms on
page 54.)
 Setting range:
from approx. 0,1% to 100%
 Setting resolution:
±1 x 10
-4
 Residual ripple (0 - 10MHz):
<1 x 10
-4
pp + 10mVpp
 Recovery time:
Voltage control:
<50µs for load changes from
10% to 100% or from 100% to
10%.
Current control:
<500ms for load changes
causing an output change of
less than 10% of the rated
voltage.
Units with output voltage
>65V, will switch off for a
short time at high and fast
load changes.
 Setting time at nominal load:
100ms to 500ms for changes
of the output voltage from
10% to 90% or 90% to 10%
 Discharge time constant for
output without load:
approx. 2sec. to 60sec., de-
pending on type
 Deviation:
For ±10% mains voltage vari-
ation:
<± 1 x 10
-5
For no load / full load:
<2 x 10
-4
Over 8 hours under constant
conditions:
<±1 x 10
-4
Within the temperature range:
<±1 x 10
-4
/K
Possible Options:
 Coarse/fine-potentiometers
(99% / 1%) for more accurate
adjustment of voltage and / or
current
 Analog programming (The
positive output has to be
earthed; see also page 44)
 Analog programming, floating
(see page 44)
 Computer interfaces - IEEE
488, RS 232, RS 422, Profi-
bus DP, USB, LAN (more on
request) (see page 46)
 Roller blades for cabinet units
 Higher stability (see page 48)
 Power limitation (see page
48)
More options and special solu-
tions on request. Some options
may involve changes to the
description of the unit - espe-
cially concerning the mechani-
cal design.