Manitowoc National Crane 500E2 Service Manual

3-2 Published 08/16/19 Control # 112-05
ELECTRIC SYSTEM 500E2 SERVICE MANUAL
the 3
rd
section sheave case. The wire then loops around the
clamp arrangement on the sheave case and routes through
access holes in the side plate of the boom. The wire
terminates at a quick connect three conductor plug designed
for anti-two-block switch or jib interface.
ANTI-TWO BLOCK INTERNAL WIRE REPAIR
In the event of a break in continuity of the anti-two-block wire
routed internally in the boom, the anti-two-block hydraulic
system will sense a problem and make certain crane
functions inoperative. Before repair or replacement of
internal wire, check for continuity loss at the anti-two-block
switch, damaged, missing, or corroded connectors and
overall system condition. Due to the environmental exposure
of the system, a thorough check of the circuit should be
performed.
The procedure for removal and reinstallation of the anti-two-
block wire can be accomplished using two different methods
depending on the severity of the damage. Alternative #1
should be used if the wire has experienced a continuity
failure in one or both of the conductors, but the rubber jacket
of the wire is still intact. Alternative #2 is to be used if the wire
has been completely cut or either end of the wire is
inaccessible.
THREE SECTION BOOM ATB WIRE REPAIR
Alternative #1
This procedure pulls the replacement wire through the boom,
following the path of the defective wire.
Special tools or equipment:
• Two end-to-end electrical butt connectors
• Shrink tube or electrical tape
Proceed as Follows:
1. Retract boom completely.
2. Loosen and remove capscrew and cable clamp
arrangement from sheave case attachment point of anti-
two-block wire. Remove quick connect plug on anti-two-
block wire by unscrewing base of plug and
disconnecting individual wires from connections. Note
pigtail length at this time and wire / terminal number
location for proper reassembly.
3. Pull end of anti-two-block wire through side plates of 3
rd
section boom to gain in-line wire path.
4. Attach replacement anti-two-block wire to damaged wire
with a temporary splice, securing the conductors with
end to end butt connectors and shrink tube or electrical
tape. This connection must be secured well enough to
pull the new wire through the boom.
5. At the hoist mount end, reach into the rear of the boom
and loosen the capscrew on the anti-two-block cable
clamp enough to let the cable run around it with minimal
effort. This clamp is located on the extend cable anchor.
6. Disassemble spade bolt anchor attaching anti-two-block
wire to the extend cable plate on the hoist mount end of
the boom.
7. Pull wire from hoist mount end. Replacement wire
temporary splice may need assistance reeving around
anti-two-block cable clamp in rear of 3
rd
section. If
excessive force is needed to pull wire through, observe
wire routing and make adjustments as needed to avoid
breaking temporary splice. If splice fails at this point,
wire routing Alternative #2 should be used.
8. Pull wire through boom, leaving enough wire on sheave
case end to properly attach and terminate wire.
9. Tighten anti-two-block wire clamp located in rear of 3
rd
section.
10. Route sheave case end of anti-two-block wire around
clamp in sheave case, and through holes in side plates.
Pulling on this end will tension the static length of anti-
two-block wire clamped in the 3
rd
. Approximately 15-25
lb (6-11 kg) will be sufficient to provide proper operation.
Tighten sheave case anti-two-block wire clamp.
11. Reassemble quick disconnect plug to anti-two-block
wire. Proper wire attachment is critical for proper anti-
two-block system operation.Consult electrical schematic
in this book for proper connector wiring.
12. Temporary splice should now be approximately 10 feet
(3 m) past the hoist mount end of the boom. Break
splices and slide strain relief/cord grip onto wire, into
approximate position inside the boom.
13. Assemble spring and spade bolt to cord grip and
reassemble anchor components to extend cable anchor
plate on the hoist mount. Slide cord grip up anti-two-
block wire into boom to increase spring tension on
moving length of anti-two-block wire. Approximately 2"
(50 mm) of spring extension tension should be adequate
for proper operation.
14. Visually inspect interior routing of anti-two-block wire for
excess slack in wire, inaccurate routing of wire, etc.
correct any problems before boom operation.
WARNING
Do not, under any circumstances, work at an elevated
height without using proper fall protection as required by
local, state or federal regulations

Manitowoc National Crane 500E2 Specifications

General

Brand	Manitowoc
Model	National Crane 500E2
Category	Construction Equipment
Language	English