G&L MMC-A2, Hardware Manual

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Standalone Digital MMC Control
112 MMC Hardware Manual G & L Motion Control Inc.
Figure 5-4: Pin Out for the 3-pin Power Supply Screw Terminal Connection
5.6 Replacing the MMC Battery
Follow the procedure below to replace the Standalone Digital MMC
Control’s battery as a preventative maintenance procedure (approximately
every 5 years) or when the Diagnostic Light flashes the “Replace Battery”
code:
1. After DC power has been applied to the Control for at least five min-
utes, turn off power. This ensures that the contents of memory will not
be lost while the battery is removed. Disconnect the input power con-
nector from the Control.
2. Remove the Control (including any optional modules) from the cabinet.
3. Use a static-free work surface if possible. Ground yourself using a
properly grounded wrist strap before you open the case. These are
standard precautions before handling any electronics component.
4. Lay the Control system on the work surface. If there are no optional
modules attached, remove the cover by removing the five screws, two
on top, two on the bottom, and one on the right side of the Control.
If there are one or more optional modules attached, remove the four
screws that attach the first optional module and remove the Control
from the Optional Modules.
5. Refer to Figure 5-5 for the location of the battery. Note how the polarity
markers are oriented.
WARNING
DO NOT touch any of the capacitors. Do not touch the pins on any
of the ICs. Even with precautions against static you may destroy the
circuitry.
+24V
COM
Power Source
24V DC
24V DC
24V DC Common
GROUND
SPG