Chapter 7
Page no. 548
JC-ELE-A-007.fm
GE Healthcare
Senographe DS
Revision 1
Service Information and Procedures Class A 2385072-16-8EN
Job Card ELE A007 - Line Resistance Measurement
2. While looking at the multimeter, press the power-on switch on the Supply Command Board 200-PL2.
During a period of 3 seconds, a resistive load (power resistors R1 and R4 on the Supply Command
Board 200-PL2) is connected across the line input, causing a drop in the voltage reading on the mul-
timeter. Note and write down this closed circuit voltage:
V
2
=....................................
Note:
After this 3 second period the red LED DE3 on the Supply Command Board 200-PL2 illuminates.
This indicates that heating of the resistive load prevents an immediate repeat reading. After about
15 minutes, the LED goes out, the reading can then be repeated if necessary.
3. Calculate line resistance R
L
according to the formula:
R
L
= [(V
1
- V
2
) / V
2
] R
INT
where R
INT
, the internal resistive load, depends on the nominal AC supply voltage V:
Voltage (V)
R
INT
(
Ω
)
200
11
208
11
220
11
240
11
4. Turn off the Senographe: set the generator power switch to the 0 position and switch off AC power.
5. Disconnect the line voltage selection wire SEL from the 0 V lug on the Mains Distribution Board 200-
PL1. Reconnect the line voltage selection wire to the lug corresponding to the nominal (not mea-
sured) AC line voltage. Tighten the lug nuts to a torque setting of 4 Nm.
Check that the calculated line resistance R
L
does not exceed the maximum value given in Table 1 for
the nominal AC supply voltage.
If the calculated value exceeds the maximum value given in Table 1, consult with the hospital electri-
cal department and your OLC. The problem must be resolved before the Senographe system is put
into service.
TABLE 1 - MAXIMUM PERMISSIBLE LINE RESISTANCE
Nominal AC voltage
Maximum Line Resistance
240 V
0.40
220 V
0.34
208 V
0.30
200 V
0.28
