Echelon DM-21 Device Manager - Manual (Page 99)

Device Manager User’s Guide A-3
• There may be excessive network cabling. See Chapter 3 for a discussion of the
maximum cable distances permissible on the twisted pair channels. If the
channel cabling is too long, install one or more LPR Routers in series with the
network cabling. Refer to the transceiver user's guides for more detailed
cabling information.
• There may be improper network cabling. See Chapter 3 for a discussion of
the types of cabling that are approved for use on the TP/FT-10 channel. In
some cases it is possible to correct network communications by installing one
or more LPR Routers in series with the network cabling. In other cases the
cabling must be replaced with an approved cable.
• There may be an excessive number of modules on a channel. See Chapter 3
for a discussion of the number of devices that can be installed on a channel.
If too many modules are on the channel, install one or more LPR Routers in
series with the network cabling.
• Modules may be connected to the wrong channel of an LPR Router. Care
must be taken to ensure that correct types of devices are connected to the two
channels of a router. LonPoint modules should only be connected to a TP/FT-
10 channel.
Troubleshooting the Device Manager Loading Wizard
"The DM named xx cannot be compressed because another DM exists in
the same subsystem hierarchy…” is displayed during compression.
There may be another Device Manager in a sub-subsystem. When a subsystem is
compressed, all the sub-subsystems of that subsystem are also compressed, as
illustrated in Figure A-1. In fact, compressing subsystem_1 is equivalent to
compressing subsystem_combine. This may conceal Device Managers that were
inadvertently associated with subsystems embedded within a subsystem.