Description - Atlas Copco XAS 185 CDU T4 Original Instructions Manual

LEGEND
F1 Circuit Breaker
G1 Alternator
G2 Battery
H1 Temperature Alarm Lamp
H2 General Alarm lamp
HTR Air inlet preheat
K0 Starter solenoid (part of M1)
K1 Relay
K2 Relay
K3 Relay
K4 Relay
K5 Relay
M1 Starter Motor
P1 Hour meter
P2 Fuel level gauge
S1 Contact switch (Off-on-overide-start)
S2 Temperature switch Engine
S3 Oil Pressure switch Engine
S4 Lamp test switch
S5 Temperature switch (Compressor)
S6 Low fuel level switch
S7 Fuel level sender
S8 Preheat Pushbutton
Y1 Fuel Solenoid Valve
R1 Resistor
V2 Diode

DESCRIPTION

Operation of the electric circuit In detail
Start button S1 position 1:
Line 2 on 12V contact K3 closed (30-87), lamp H2 is
on. K4 excites contact K4 (87-87a). Thermocontact
element S5 normally closed, K1 excites contact K1
(30-87).
Use of preheat:
Start button S1 position 1 press pushbutton S8,
energizes relay K5 and provides power to the glow
plug.
Start button S1 position 2:
Line 3 on 12V (override function) hour meter P1,
and fuel solenoid Y1 is excited. Thermocontact
engine S2 normally closed, oil pressure contact S3
open.
Start button S1 position 3:
Start relay K0 is excited and starter motor is running,
engine builds up oil pressure and oil pressure
contact S3 closes. K3 excited and contact K3
changes over to (30-87). Relay K2 no longer
excited, contact K2 opens, lamp H1 goes out.
Alternator also commences supplying voltage and
K4 is no longer excited and contact K4 changes over
to (87-87a). Lamp H2 goes out, one can release
start button S1 and it returns to position 1. Exciting
the safety devices occurs no longer across line 3 but
across line 2 to line 4 and this way to line 3.
Explanation of shutdowns:
Oil pressure contact S3 opens, K3 no longer
excited. K3 changes over (87a-87), engine cuts out
because fuel solenoid Y1 no longer excited and
lamp H2 goes on simultaneously.
Thermocontact S2 opens, K3 no longer excited. K3
changes over (87a-87), engine cuts out because
fuel solenoid Y1 no longer excited and lamp H2
goes on simultaneously.
Thermocontact S5 opens, K1 no longer excited.
- 21 -
Contact K1 changes over (87-87a). K3 no longer
excited. K3 changes over (97a-87), engine cuts out
because fuel solenoid Y1 no longer excited and
lamp H2 and H1 go on simultaneously. Take-over
relay K2 is excited simultaneously with H1 and
contact K2 closes (30- 87).
Thermocontact S5 cools off and closes, K1 excited
again and contact K1 changes over (87-87a).
However, lamp H1 remains on across line 9 and
contact K2 (30-87).
A fault in the alternator part causes terminal D+ to
go to 0V and K4 to be excited. Contact K4 changes
over to (87a-87), engine cuts out because fuel
solenoid Y1 no longer excited and lamp H2 goes on
simultaneously.