Zeiss humphrey HFA II-i series, Руководство по обслуживанию на месте

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PROPRIETARY and CONFIDENTIAL
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SERVICE
BULLETIN
Instrument:
Humphrey Field Analyzer II-i No.: FA2i-044A
Subject: Power Supply P/N F57974 Date: 12 Feb 08
Status:
Mandatory – Check Next Visit Pages: 2
Problem
The HFA II-i Power Supply, P/N F57974, has a potential to fail under moderate load conditions.
Cause
The Power Supply diodes, rated at 100 Volts, can experience voltages exceeding 100 Volts. If the
voltage exceeds the 100 Volt rating, the diode(s) may fail, causing the Power Supply to fail as well.
Solution
The Power Supply manufacturer has determined that replacement of the 100 Volt rated diodes, with a
150 Volt rated diodes, prevents diode and Power Supply failure. The manufacturer has incorporated the
150 Volt diodes on all new and reworked Power Supplies.
Power Supply Replacement
To determine if the HFA II-i instrument has an affected power supply:
1) Verify that the instrument serial number is in the range shown in Table 1. If the serial number is
NOT shown in Table 1, the instrument is not affected. No action is required.
2) If the instrument serial number is in Table 1, inspect the label on the power supply. If the label is
as shown in Figure 1, the power supply has the 100 Volt diodes. In this case, replace the power
supply.
3) Order part number F57974.
4) If the label is as shown in Figure 2, the power supply has been reworked with the 150 Volt diodes.
No action is required.
Table 1: The Affected Serial Number (S/N) Range of HFA II-i Instruments
Model Serial Number Range
720i 8006 - 8177
740i 16212 - 16550
745i 6131 - 6259
750i 11586 - 11842
Note - Credit will only be given for Power Supplies that meet the above stated criteria, which have been
returned to CZMI for inspection by September 30, 2008.