KEP ES-756, Installation & Operating Instructions Manual

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3
WIRING
WIRING CONNECTIONS
AC / DC CONNECTIONS:
NOTE: Connect power only after other con-
nec tions are fi n ished. Do not touch the live AC
power ter mi nals. The unit has been de signed
with an isolated AC input, therefore polarity is
not a concern for the AC power. The chassis
is plastic, therefore earth ground is not used.
For DC operation, cDC to terminal 10
and -DC to terminal 3.
Although the unit is designed to be im mune
from line or RF interference, the unit is con-
trolled by a microprocessor and an elec tri cally
"noisy" environment could cause op er at ing
problems. The input power lines should not
be com mon to power lines for motors, pumps,
contactors, etc.
Four sources of noise can occur:
1) AC power line noise- If the unit cannot
be connected to an electrically clean power
source, an inductive load suppressing device
(MOV as GE#V130LA1 or Resistor Capacitor
as Paktron# .2uf/220 ohm @ 400V) can be
installed. Although locating the suppressor
across the AC supply at the unit should help,
best results are obtained by connecting the
suppressor across the leads of the "load" at
the device causing the spikes.
2) Input line noise- The noise is carried on
the input and DC ground lines. Make sure
the input wires are not run into the unit in a
bundle with power input lines. We recommend
using shielded cable. Connect the shield to
DC signal ground of the unit and "earth" at one
point in the circuit preferably at the DC ground
ter mi nal of the unit.
3) Output lines- The unit has two open col-
lec tor outputs. When these outputs are used
to run external relays or solenoids, spikes can
be generated upon activation. This noise can
spread through the instrument causing operat-
ing problems. If the source is a D.C. operated
device, a gen eral purpose diode (IN4004)
placed across the solenoid prevents electrical
noise spikes. Connect the cathode (banded
side) to the more positive side of the coil. If
the source is an A.C. operated device, use a
Resistor Ca pac i tor or MOV across the coil.
4) 24 VDC output supply- Noise can be gen-
er ated on the 24 VDC output supply if it is used
to drive inductive loads or if the current draw
exceeds 50mA. Insure that all inductive loads
have a diode (such as IN4004) across the coil
and that the current does not exceed 50mA.
REAR VIEW
1 2 3 4 5 6 7 8 9 10 10 11 12 12
13 13 14 14 15 15 15 15 17 17 18 18
1• Reset In
2• Analog Out (Sink)
3• Signal GRD (-DC)
4• (Current) +I in
5• (Voltage) +V in
6• Not Used
7• +24V Out
8• Preset B Collector
9• Preset A Collector
10• +DC In
11• AC Neutral
12• AC Line