Siemens LMV5 Quick Start Manual page 127

Section 5 Troubleshooting
Common Problems 5-1
The most frequent source of problems concerning the LMV5 is wiring errors, followed closely by
parameter setting errors.
This section details the most commonly seen problems, along with the most common solutions to
these problems. Section 5-2 includes a list of error codes that have associated corrective actions.
CANBus Wiring
The majority of all wiring errors are related to the CANBus.
The CANBus system includes: the AGG5.210 transformer, the two 12VAC fuses in the LMV5,
the AZL5, the special CANBus cable, the actuators, additional transformers (if required), and the O2
module (if equipped).
If an error occurs with any CANBus connected device, the following 5 items should be checked:
1) The wiring on the AGG5.210 transformer, specifically how the four pin connector X52 is wired to
the LMV5. Most problems occur on Pins 3 and 4 of the transformer. Pin 3 on the transformer
and terminal X52.4 on the LMV5 should be wired to PE (Protective Earth or Panel Ground).
Pin 4 on the transformer should be wired to X52.3. (See Wiring, Section 3)
2) The CANBus connection between the AZL and the LMV5 is factory pre-made, has different
color wires, and is 9 foot long. The CANBus connection between the LMV5 and any actuator or
PLL module is: 12VAC1 Red 16 AWG, 12VAC2 Black 16 AWG, CANH Blue 24 AWG, CANL
White 24 AWG, GND Green 20 AWG, and shield. Ensure that no wire strands from adjacent
pins on the CANBus plugs make contact. No conductors, only insulation should be visible when
viewing a properly terminated CANBus green plug.
3) The shielding of the special CANBus cable. The shielding of this cable is immediately under the
plastic sheathing of the cable and the shielding encircles all the conductors. All shielding, on all
segments, of the CANBus cable must have continuity with terminals X51.1 (for the actuators,
O2 module) or X50.1 (for the AZL). This can be checked with a multi-meter connecting one
probe on the shielding clip attached to terminal X50.1, and one probe on the last device of the
CANBus. Shielding clips (AGG5.110) are required (one for X51 and if not using a pre-made AZL
cord, one for X50) to mount and terminate the shield of the CANBus cable on the LMV5 end.
The continuity of the shield is maintained thru each of the actuators and / or O2 module by using
the metal shielding clamps provided on each device.
(See wiring, Section 3)
4) CANBus fuses, FU2 and FU3, located on the right hand side of the LMV5. Check that these
fuses are not blown. If any are blown, check the wiring for incorrect terminations. Also check
the area of the cable where the sheathing was stripped. It is possible that a knife was used to
cut the sheathing, and that the knife penetrated through the cable sheath, the shielding, and the
insulation on 12VAC1 or 12VAC2. If the shield makes contact with either 12VAC1 or 12VAC2 a
short will result. This will blow fuses, and can damage actuators or O2 module.
5) Electrical loading of the CANBus. The 12VAC1 and 12VAC2 power is supplied by the
AGG5.110 transformer connected to the LMV5. The output of one transformer is sufficient for
many applications, but some may require two transformers. CANBus loading can be determined
useing of the CANBus loading table, found in Section 3-1.
Wiring of the second transformer can be found in Section 3-3.
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