Manitowoc National Crane NBT40 Series, Service Manual

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National Crane
Published 8-01-2017 Control # 287-11
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NBT40 SERVICE MANUAL ELECTRIC SYSTEM
VEC MODULE
The Vehicle Electrical Center (VEC) module (8, Figure 3-6)
is located in an enclosure on the boom rest above the front
outrigger manifold. The VEC module contains the following
relays and circuit breakers:
• Truck ignition relay (1) disables the truck ignition when
the engine is started from the crane cab or with the radio
remote. The engine cannot be turned off from the truck
cab when this relay is energized.
• Oil cooler relay (2) powers the oil cooler fan when the oil
temperature switch closes.
• Throttle control relay (3) switches the throttle control
from the truck to the crane. The radio remote option
disables this relay when the truck is started with the
radio remote.
• The engine start relay (4) energizes the engine starter
circuit from the crane cab ignition or radio remote.
• Item 5 not used.
• Crane Ignition relay (6) disables the crane ignition switch
when the truck is running.
The outrigger control relay (7) provides power for ground
level outrigger control. When the crane function power
switch is energized, the ground level outrigger control is
disabled.
Item Relay
1 Truck Ignition
2 Oil Cooler
3 Throttle Control
4 Engine Start
5 Outrigger Power
6 Crane Ignition
7 Outrigger Control
1
2
3
4
5
6
7
FIGURE 3-6
8
Reference Only