For optimal reliability, apply a small amount of Loctite 242 Medium Strength threadlocker to the
threads of each screw. Torque screws between 3 in-lb. and 5 in-lb.
SERIAL PORT 3 CONFIGURATION
Serial Port 3 is configured as RS485 Half Duplex (2-Wire). Configuration features are found on the 12001
carrier board near the protection fuse via SW2 and J4. See the Serial Port 3 Operation section for detailed
configuration options.
INPUT CURRENT PROTECTION FUSE
The fuse holder located at location F2 is located on the positive power input path of the 12001 carrier
board. To protect the user and the computer system from major system faults, the system is designed to
have the fuse fail if DC current of 10A or greater is present.
The R4 uses an automotive style Mini-Blade Fuse (Littelfuse PN 0997010.WXN).
To replace the fuse:
1.
Follow the steps found in the Access Serviceable Parts section above to access the fuse.
2.
Once exposed, grip the fuse and wiggle it back and forth while pulling up until the fuse slides out of
the holder.
3.
Place the blades of the new fuse in the holder and press it straight down into the holder until the
blades are completely hidden by the fuse holder contacts.
©Sealevel Systems, Inc.
R4 Manual
34
SL9260 06/2015
