DELTA ELEKTRONIKA BV
SM3000
Page 4 - 2
OPERATING MAINTENANCE TROUBLE SHOOTING CALIBRATING
1991, rev. May 2008
5)
STATUS OUT PUTS
•
The status outputs have a separate Ø con nection (pin 8) to
avoid un wanted offsets in the pro gramming. This pin is pro -
tected with a 650 mA fuse (F601 on P432).
6)
RE MOTE SENSING
•
Remove the links on the SENSE BLOCK (on rear panel) and
connect sense leads (thin
shielded
mea suring wires) to S+
and S– (see fig 4 - 5 and fig. 4 - 6).
•
With remote sensing the voltage on the load can be kept con -
stant. The voltage drop in the load leads will be com pensated.
This feature is not rec ommended for normal use, be cause it
can eas ily give prob lems.
•
Max. 2 V per load lead can be compensated. Note that the
voltage drop in the leads de creases the max. output voltage
rating. In fig. 4 - 7 can be seen that on a 15 V power sup ply
only 11 V will be available on the load when 2x 2 V com pensa-
tion is used.
•
In or der to pre vent in terference it is ad visable to twist the
sense leads. To min imize the inductance in the load leads
keep the leads close to each other. The in ductance of the
loads leads could give a prob lem with pul sating loads. In this
case a large electrolytic ca pacitor (Cd) in se ries with a damp -
ing re sistor (Rd) both in parallel with the load will help (see fig.
4 - 6). Check that the ca pacitor Cd in combination with the load
leads and re sistor Rd forms a well damped cir cuit.
•
Since the
volt me ter
is in ternally con nected to the sens ing ter -
mi nals, it will au to mat i cally in di cate the
voltage on the load
.
Note that the voltage mea sured on the load will be lower than
on the out put terminals.
•
The Over Volt age Pro tector mea sures the volt age on the out -
put terminals, so the OVP set ting should be in creased by the
total voltage drop in the load leads.
7)
BAT TERY CHARGER
•
The CV / CC reg ulated power supplies are ideal battery charg-
ers. Once the output is set at the correct voltage the bat tery
will charge con stantly with out over charging. This can be use -
ful for emer gency power systems.
•
Pro tec tive mea sures
Use a CIR CUIT BREAKER in se ries in or der to pro tect the
power sup
ply from
ac ci den tal re
verse con
nec tion
(see
fig. 4 - 8). The cir cuit breaker should have a DC voltage rat ing
2x the bat tery voltage. Use the very fast type (Z), a type meant
for pro tect ing semi con duc tors.
The unit has a re verse di ode in par allel with the out put, this di -
ode and the wir ing can not with stand the thou sands of am-
peres sup plied by a wrongly connected battery.
Suggested circuit breakers for pro tection power supply
Model
Type num ber
circuit breaker
Brand Re marks
SM 15-200 D HTI102 B 100
GE
2 poles par allel
SM 30-100 D HTI102 B 100
GE
SM 45-70 D
HTI102 B 100
GE
SM 70-45 D
S281 UC-Z 50
ABB
SM 120-25 D S281 UC-Z 25
ABB
SM 300-10 D S282 UC-Z 10
ABB
2 poles in se ries,
ex tra par al lel
di ode on
out put needed
=OP TION P023
•
Re mote sens ing
can not be rec ommended, be cause it easily
causes de fects in side the power sup ply in case of wrong con -
nec tion.
If you re ally need re mote sensing, please use the cir cuit (see
fig. 4 - 9). The in ternal cir cuit can be protected by rel atively
small anti-parallel di odes. To pro tect the anti-parallel di odes,
please con nect the fuses in series as in dicated in fig. 3 - 9 . A
practical choice for the fuses is 250 mA, the di odes can be any
normal 3 or 5 A type.
fig. 4 - 5
Lo cal sens ing
fig. 4 - 6
Remote sensing with shielded wires
fig. 4 - 7
Remote sensing, voltage drop in load leads sub -
tracts from max. output
fig. 4 - 8
Charging battery with a circuit breaker in se ries
fig. 4 - 9
Protecting sense wires with di odes
