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No. 99MBC071A
6. INTERFACE UNIT
b. When an external power source of +24V is used and the display of judgment result on GO
and ±NG LEDs is triggered by the key operation at the external device.
2
17
+24V
Connector pin No.
COM(IN)
COM(IN)
20
35
0V
COM(OUT)
COM(OUT)
3
21
4
22
5
6
24
7
25
8
26
14
PROG0
PROG1
PROG2
PROG3
PROG4
SHIFT
PRINT
RUN
RESET
0.5W
2.2K X 3
LED
-NG
GO
+NG
c. When the circuit has the same specification as described on the previous page and powers a
lamp (1A maximum) when a ±NG judgment takes place
8
17
+24V
Connector pin No.
-NG D1 D1
+NG D2 D2
14
35
0V
LAMP
COM(OUT)
COM(OUT)
Q1
R1
PNP Darlington transistor,
e.g. 2SB975 (Manufacturer: NEC)
Protective resistor, 5W, 1 to 2Ω
Switching diode, e.g. 1S188
(Manufacturer: Toshiba)
Q1:
R1:
D1:
D2:
NOTE 1. Approximately 10 times the rated current will flow through the lamp when it is
turned on. (This is called “rush current”, which is often observed when the lamp
filament resistance is low because of low temperature.) So, the ICMAX of the
driving transistor should have a sufficient rating.
2. About 1.5W dissipates from the transistor in the above diagram. A radiator panel
is needed.
