Troubleshooting; Power Supply And Voltage Distribution - Dräger Narkomed 2C Technical & Service Manual

NM2C
3.0

TROUBLESHOOTING

This section contains information to assist the North American Dräger qualified
Technical Service Representative (TSR) in locating electrical faults affecting the
NARKOMED 2C monitoring and display devices. Since most troubleshooting efforts
begin with verifying power supply voltages, the following paragraph outlines the
voltage distribution scheme within the machine along with test points for each of the
voltages.
3.1

Power Supply and Voltage Distribution

In the NARKOMED 2C, +5VDC, +12VDC and -12VDC are supplied to J15 on
the processor board; +8VDC is supplied to J4 on the alarm channel and is also
distributed to the ventilator controller via J3 on the alarm channel. These
voltages can be measured at the connectors shown in Figure 3-1. Table 3-1 lists
the acceptable range for each voltage under normal load conditions. Figure 3-2
shows a block diagram of the NARKOMED 2C, including the primary and
secondary voltage distribution scheme.
TABLE 3-1: TEST POINTS AND ALLOWABLE RANGES
PROCESSOR
J15-14 (Pur)
J15-13 (Orn)
J15-15 (Blk)
ALARM CHANNEL
PROCESSOR BOARD
CONNECTOR J15
(TOP VIEW OF CONNECTOR
AS SEEN FROM FRONT
OF MACHINE)
Figure 3-1: POWER SUPPLY TEST POINTS (REAR VIEW OF CONNECTORS)
Rev. U
RETURN TO THIS MANUAL'S TABLE OF CONTENTS
J15-4 (Yel)
J3-9 (Wht)
J3-3 (Orn)
13 14 15
10 11 12
7 8 9
4 5 6
1 2 3
RETURN TO CD-ROM TABLE OF CONTENTS
TROUBLESHOOTING GUIDE
VOLTAGE ACCEPTABLE RANGE
+ 5 VDC 4.85 to 5.15 VDC
+ 12 VDC 11.76 to 12.24 VDC
- 12 VDC -11.64 to -12.36 VDC
Common
VOLTAGE ACCEPTABLE RANGE
+ 8 VDC
Common
ALARM
CHANNEL
CONNECTOR J3
3-1
7.76 to 8.24
7 8 9
4 5 6
1 2 3
SV50556