Replacing Power Supply 08PSS3401T (for Retrofit Kits 08PSS3401N and 08PSS3401X)
PELLERIN MILNOR CORPORATION
2.
By processor board number and revision level
—As shown in Figure 2, the processor board
part number and revision (rev) level are printed on the board. Compare the part number and
rev level of your processor board with the list in Table 1 to determine if your board has the
resistor on board:
Table 1: Processor Boards Commonly Used on Machines With 08PSS3401T Power Supply
Part Number
Inclusive Rev Levels
Resistor Included
08BNCMPAT
All
NO
08BNCMPADT
All
NO
A through I
NO
08BN785AT
J and later
YES
A through I
NO
08BN785ADT
J and later
YES
A through E
NO
08BN788AT
F and later
YES
08BH18EPT, 08BH18EACT,
08BH18EPAT, 08BH18EPBT,
08BH18EPCT, 08BH18EPDT,
08BH18EPXT, 08BH18EPYT
All
YES
3.
By measuring the resistance across the board
—Disconnect the processor board from the
power supply if this has not already been done. With an ohmmeter, measure the resistance
5VDC and signal ground (pins 3 and 10 on the 10 pin connector, as shown in Figure
3). The resistor is connected in parallel with +5VDC circuit so if it is present, the resistance
will measure approximately 15 ohms. If the resistor is not present, the reading will be much
higher (over 1000 ohms).
3.
Electrical Connections
The procedure for making electrical connections will vary somewhat with the kit supplied, type
of machine, and the type of power supply being replaced. However, except possibly for wire
color codes, the schematics shown in Figure 3 cover all situations. (Older machines may use
different wire color codes, but the pin numbers will be the same as shown in this figure.) Consult
the original schematic manual for wire colors on an older machine or contact the Milnor factory.
CAUTION 3 : Component Damage Hazard
—Wire V3, which supplies -12VDC, is not
used on certain machines (e.g., machine models ending in C4A, M4A, or M4E, as well as
machines that use neither an A/D (analog-to-digital), nor a D/A (digital-to-analog) board).
• If unused, terminate this wire with a wire nut to prevent shorting.