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8-35
62-11039
7. If the suction pressure rises during Step 5., or if the
valve is determined to be stuck closed in Step 6., turn
the unit Off by placing the SROS in the OFF position
and unplug the 4 pin connector to the SMV. With a
reliable digital ohmmeter, check the winding resist-
ance between 1A (Black) wire and the 1B (White)
wire AND between the 2A (Green) wire and the 2B
(Red) wire. In normal ambient, each winding should
have 72 to 84 ohms. If this resistance is confirmed,
proceed to Step 8. If an infinite or zero ohm reading
occurs, first check the wires at the connector for
good contact. If the connector is in good condition
and the resistance is still bad, one (or both) of the
coils could be faulty. Replace the SMV power head
assembly P/N 14--00263--20.
Refer to Section
8.23.3.
8. Locate the wires on the engine harness side of the
SMV connector. Locate the wires labeled CSMVA,
CSMVB, CSMVC and CSMVD. These will correlate
to the connector pins labeled A, B, C and D. See
Table 8-7.
9. Place the SROS in the Start/Run position. DO NOT
ALLOW THE UNIT TO START. When the Message-
Center displays “SMV CLOSING”, measure the AC
voltage between pins A and B and then between C
and D. A reading of 10 to 16 VAC should be read by
the digital voltmeter for each pair of wires. If this test
passes, there is a good signal coming from the mi-
croprocessor.
10. If the reading of 10 to 16 VAC is not present on one or
both of the wire pairs, check the wiring between the
microprocessor and the SMV connector, or check
the microprocessor for proper model number config-
uration.
11. If all the above tests pass, the SMV is operating
properly and the abnormal unit operation can be con-
tributed to something other than the SMV.
8.23.3
Replacing
The
SMV
Power
Head
(14--00263--20)
a.Pump the unit down at the manual shut off valve (king
valve) (Refer to Section 8.10.1).
b.Unplug the SMV connector from the engine harness.
c.Loosen the 2 1/8” nut on the SMV and remove the
power head assembly. (See Figure 8--34).
d.Install the new SMV power head.
e. The power head should be set to 100% (Open) when
received from the warehouse. This is to ensure the
Teflon valve seal is not damaged when it is installed.
Ensure the valve is fully open by using Stepper Motor
Tester (CTD special tool P/N 07--00375--00) to manu-
ally open the valve to 100% before it is installed.
f.Torque the 2 1/8” nut to 35 to 40 ft--lbs (4.8 to 5.5 Mkg )
g.Reconnect the SMV connector to the engine harness.
NOTE
Place unit in Service Mode before pumping
down and/or removing the refrigeration charge.
Refer to Section 5.2.3.
h.Evacuate the low side of the refrigeration system. (Re-
fer to Section 8.12)
i.Open the king valve, run the unit for approximately 10
minutes and initiate a pretrip.
d. Emergency repair procedures :
In the event that the SMV system has a failure, and
replacement components are not readily available in an
emergency. A
LIMP-HOME
procedure can be done as
follows :
1. Attach a manifold gauge set.
2. Perform a low side pump down. When the unit has
reached 0 to 5 psig close the suction service valve
and turn the unit OFF.
3. Remove SMV powerhead by loosening the 2-1/8
inch diameter nut (see Figure 8--34), and sliding the
powerhead out.
4. Remove the piston by loosening the Allen screw and
removing the piston and screw.
5. Install the powerhead assembly (without the piston),
torque to 35 to 40 foot-lbs (4.8 to 5.5 Mkg).
6. Open all valves.
7. Start the unit.
8. Adjust the suction service valve so that the approxi-
mate temperature OR current limit is maintained.
For perishable loads, it is recommended that the ad-
justment be made so that the available capacity is
slightly larger than the load, the unit will cycle OFF
and ON.
9. Once repair parts become available, repair as re-
quired.
8.24 CHECKING DEFROST OR HEATING CYCLE
NOTE
The DTT temperature for any enabled
compartment must be 40
°
F (4.4
°
C) or cooler,
before any checks can be made.
8.24.1 Defrost Air Switch
a. To check the Defrost Air Switch, run unit in high speed
cooling and jump across the air switch terminals. This
will start the defrost cycle as it simulates the action of
the defrost air switch. Bypassing the switch in this
manner operates all components involved in defrost.
NOTE
If none of the DTTs are below 40
_
F (4.4
_
C), the
MessageCenter will show
“CANNOT START DEFROST CYCLE”.
b. Unit should remain in defrost until all DTTs reach
55
_
F (12.8
_
C). At this point the defrost cycle will ter-
minate, and the unit will resume automatic opera-
tion.
c. If the above test indicates satisfactory operation, test
DAS settings using a Dwyer Magnehelic gauge (P/N
07-00177) or similar instrument. (Refer to Section
8.25)
Summary of Contents for VECTOR 1800 MT
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Page 2: ...OPERATION SERVICE MANUAL for VECTOR 1800 MT Trailer Multi Temp Refrigeration Units ...
Page 19: ...1 5 62 11039 1 3 SAFETY DECALS ...
Page 20: ...1 6 62 11039 62 03958 00 Heat Warning 62 03957 01 High Voltage 62 60280 00 Standby Safety ...
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Page 310: ...10 8 62 11039 BASED ON ENGINEERING SCHEMATIC 62 60926 REV G NEXT SHT ...
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