56
section 6
troubleshootinG
K3 and K33, activated by supplying a Contactor Signal, initiate and controls the operation of K2 (Starting Contactor) and
K4 (Pilot Arc Contactor). K3/K33 are called the Auxiliary Main Contactors because they must be activated before the
Main Contactor (K1) power-up sequence can occur. The Contactor Signal is supplied through a remote contact connect
-
ing 115VAC from J1-R to J1-M. If K6 is closed (no fault), K3 will activate. The closing of K3(6, 9) activates K2, the Starting
Contactor, and K4, the Pilot Arc Contactor, provided the power source is not over heated. See Subsection 6.7, E-stop and
Main Contactor Circuits for more information on the operation of K2. K4 is turned off when the Current Detector senses arc
current and opens the contact connecting P2-5 to P2-6 on the Control PC Board.
In addition to operating K3/K33, the Contactor Signal also activates the Solid State Contactor. The Solid State Contactor is
a logic and interlock circuit permitting the IGBT’s to conduct whenever the remote Contactor Signal is present. The 115V
AC Contactor Signal is fed to TB1-9, TB7-8, and resistors R45 and R45A. These resistors reduce the 115V to approximately
16V AC fed into the Control PC Board at P6-1 and P6-2. The Control PC Board sends a signal to both the Left and Right PWM
/ Gate Drive PC Boards. Illumination of LED3 on both of the PWM / Gate Drive PC Boards is indication that the Solid State
Contactor is functioning.
6.6 auxiliary main contactor (k3 & k33) and solid state contactor circuits
K33 K15
6
6 9
R45B
TB7-8
TB7-9
P6-1
TB1-9
K3
K2
K4
P2-5
P2-6
TB1-7
K33
J1-Z
TB9-16
TB9-13
TB9-18
P1-9 P1-10
680
P6-2
K3
K7
6
6 9
9
ON/OFF
IGBT DRIVE
ON/OFF
LED3
LED3
LEFT PWM/GATE
DRIVE PC BOARD
RIGHT PWM/GATE
DRIVE PC BOARD
+15V
CONTROL
PC BOARD
Solid State Contactor
T
(AMC)
K6
9 6
NEUT
RA
L
H
O
T
I
N
FN4
J1-R
J1-M
115V
4
1
2
AC
STARTING
CONTACTOR
PILOT ARC
CONTACTOR
3
H
Current Detector
Contact on
Control PCB
Fault Relay
115V AC
IGBT DRIVE
J1-H
AUXILLARY MAIN CONTACTOR (K3 & K33) & SOLID STATE CONTACTOR CIRCUITS
Open with fault or
main line power off
Over Heat Relay - Closed
during normal operation
R45A
8W
10K
P1-9 P1-10
TB7-8
P10-5
P10-6
P11-5
P11-6
8W
10K
TB8-7
TB1-8
CONTACTOR SIGNAL
CONTACTOR SIGNAL
Summary of Contents for Plasmarc EPP-450
Page 1: ...0558007944 08 2014 Plasmastrømkilde Instruktionsbog DA EPP 450 ...
Page 3: ......
Page 4: ...4 ...
Page 63: ...63 section 6 TROUBLESHOOTING ...
Page 65: ...65 notes ...
Page 66: ...66 notes ...