Maintenance & Trouble Shooting - Delta Elektronika ES300 Series Manual

MAINTENANCE & TROUBLE SHOOTING
4 MAINTENANCE & TROUBLE
SHOOTING
4.1 GENERAL
 The ES-series power supplies normally need no maintenance
or calibration. Only care must be taken that the cooling of the
unit is not obstructed.
 If required, the full scale indication of the V-meter can be
calibrated with trimpotmeter R480, the I-meter with R490.
4.2 NO OUTPUT (normal operation)
 Remove load from output.
 Check position of prog. switches at the rear panel, they
should be on MANUAL.
 Switch on unit.
 Turn both the CV and CC potentiometer a few turns clock-
wise. A voltage should be present on the output.
4.3 PROGRAMMING DOES NOT WORK OK
 Check position of prog. switches at rear panel.
 The unit works OK in manual control, but in programming
mode the output voltage / current has a large error.
 Probably the fuse in series with Ø (pin 1) of prog. connector
tripped, the fuse (F400 = 650 mA) is a self-resetting type.
 To check the fuse (F400) measure the voltage between Ø
and the minus output, during the fault condition. The voltage
should only be a few mV, a high voltage means that an
unwanted current is flowing through pin 1 of the prog.
connector.
 Please check why current is flowing through pin 1 (see also
next paragraph and fig. 4 - 1).
4.4 PROGRAMMING OFFSETS
 Unwanted offsets in the programming can be caused by
earth loops.
 Fig. 4 - 1 shows a typical earthing problem. In case the load
has a connection to earth and the programming source as
well, problems could occur. Improper choice of the earthing
point of the load can give a voltage drop of ΔV1.
 Connecting the minus or zero to a separate earth connection
can give a voltage drop of ΔV2. Because the internal wires of
the programming input are thin, the voltage drops ΔV1 and
ΔV2 will be accross the internal wiring as well. Resulting in a
error voltage in series with the programming voltage.
 The best solution for this is using a floating programming
source with the help of the ISO AMP MODULE or a floating
load.
4.5 STATUS OUTPUT FAILS
 Check fuse F401 in series with Ø (pin 8 of programming
connector). To check the fuse measure the voltage between
Ø and the minus DC Power output, a high voltage means too
much current is flowing through the fuse. F401 = 650 mA -
self resetting.
4.6 MASTER / SLAVE PARALLEL PROBLEMS
 Accidental interruption of a minus lead of a unit during
operation will cause fuse F400 to blow. To check the fuse,
measure the voltage between Ø (pin 1 of prog. conn.) and the
minus DC power output, the fuse is a self resetting type.
F400 = 650 mA self resetting. If the voltage is too high, too
much current is flowing through it.
 Check link between pin 9 and 11 on the programming
connector of the slaves.
4.7 NO LEDS on.
 Overheating can be the cause, cooling down will reset the
thermal protection.
 Check input power.
 Check fuses inside unit.
10 / 13 DELTA ELEKTRONIKA B.V.
F400
Warning! 0Vprog. and Minus DC power
are internally connected.
ES300
rev. Sept. 2019