Danfoss 51 Series User manual

MAKING MODERN LIVING POSSIBLE
Service Manual
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Service Manual Series 5t and 51-1 Motors Service Manual
Gauge information
M3 Servo pressure minimum angle 600 bar fi 0,000 psil
9/16-18 O-ring fitting
M4 Servo supply pressure maximum angle 600 bar [10,000 psi]
9/16-18 O-ring fitting
M5 Servo supply pressure 600 bar [10,000 psi]
9/16-18 O-ring fitting
Pressure measurements
Series 51-I motors
Side port
Sysem pressure B
port M2
Guage port Ml
Main
port B
System pressure A+B
Guage port M1+M2
Gauge information
M1 System pressure port A600 bar [10,000 psi]
9/16-18 O-ring fitting
t f008567. Rev BA . June 2014
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Service Manual Series 51 and 5l-1 Motors Service Manual
Initial startup procedures
Procedure
Always follow this procedure when starting-up a new Series 51 or Series 51-1 installation or when
restarting an installation in which eitherthe pump or motor has been removed.
,& warnimg
Tlris service r:rocedure may require disabiing the vehicle / rnachine (raising the rarheels cf"f the ground,
rJisconnectinq work function, and so forth) v,rhile performing, to prevent injury to the teclrnician anil
bystanders. Take the necessary safety grrecautions.
1. Before installing the motor and/or pump, inspect the units for damage incurred during shipping and
handling.
2. Make certain all system components (reservoir, hoses, valves, fittings, heat exchanger, and so forth)
are clean before filling with fluid.
3. Fillthe reservoir with recommended hydraulic fluid. Filter using a 10 micron (nominal, no bypass)
filter into the reservoir. Using contaminated fluid may damage components which may result in
unexpected vehicle/mach ine movement.
4. Fill the inlet line leading from the reservoir to the pump.
5. Check inlet line for properly tightened fittings
6. Make sure the inlet line is free of restrictions and air leaks.
7. Fillthe motor and/or pump housing with clean hydraulic fluid before start up. Fill by pouring filtered
oil into the upper case drain port.
i& caution
itlever start the prime mover unless the motor and pump are filled cornpletely with clean hyclraulic
fh-rid.
8. lnstall a G60 bar [0-1000 psil pressure gauge in the charge pressure gauge port of the pump to
monitor the charge pressure during start-up.
9. Disconnect any external control input signal (linkage for MDC, hydraulic lines for HDC, or electrical
connections for EDC) from the pump control until after initial start-up. This ensures that the pump
remains in its neutral position.
10. Use a common method to disable the prime mover. Jog (slowly rotate) prime mover until charge
pressure starts to rise.
1 1. Enable prime mover. Start the prime mover and run at the lowest possible speed until charge
pressure is established.
"& warning
Do not start the prime mover unless the pump is in neutral position {swash plaie at 0" anqle). Take
necessary precautions to prevent machine movement in case pump is actuated in stroke durinq
initiai start-up.
lf necessary, bleed excess air from the high pressure lines through the high pressure sysrem gauge
port.
12. Once charge pressure is established, increase speed to normal operating speed.
Charge pressure should be as indicated in the
and determine cause. See Troubleshootino on pump model code. lf charge pressure is low, shut down
page 29.
1.,- C*uti*n
Low charge pressure may affect the operators ability to controlthe machine.
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service Manual series 51 and 5l-l Motors service Manual
Initial startup procedures
13, shut down the prlme mover.
14. Connect the external control input slgnal.
15. Reconnectthemachinefunction if disconnected earlier.
16. Start the prime mover, checking to ensure the pump remains In neutral.
17. che.kfol forward and reverse machine operation, with the prime mover at nomal operating speed,
charge pressure may decrease slightly during forward or reverse operation.
18. Continue to cycle slowly between forward and reverse for at least five minutes.
19. Shut down prime mover.
20, Remove gauges.
21. Plug the gauge ports.
22. Check reservoir level.
23, Add filtered fluid to the reservoir, if needed.
The motor / transmission is now ready for operation.
t 1008567 . Rev BA . June 2014
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Service Manual Series 51 and 51-1 Motors Service Manual
Troubleshooting
Sluggish system
System operating hot
Excessive noise or vibration
Check Cause Corrective action,,
1Controlorifices Blocked or restricted orifice will cause sluggish
response. Orifices installed to the wrong locations
will cause PCOR controlto be sluggish.
Remove, inspect and clean all orifices. Ensure the
appropriate orifi ces are installed.
2. Threshold setting (proportional
controls) Inappropriately high threshold setting will shift the
motor at the wrong tlme. Checkthreshold setting. AdJust if necessary.
3. Control spoolor piston A sticky 4-way spool or control piston will cause
sluggish response. Clean and inspect the 4-way valve spool and control
piston. Replace if necessary.
4. Pressure com pensator setting Inappropriately low pressure compensati ng setti ng
will shift motorto maximum displacement at lower
pressure
Check pressure compensator setting. Adjust if
necessary.
5. Control input signal An improper or erratic input signalto the control
may cause sluggish response. Check input signal or electric current and correct if
necessary.
Charge pressure lnappropriately low pressure setting at loop
flushing relief valve may cause improper supply
pressure to motor control.
Measure change pressure in forward and reverse.
Adjust loop flushing relief valve if necessary.
1System pressure Inappropriately low system pressure setting may
cause sluggish response. Measure system pressure. Adjust pump pressure
limiter or system relief valve if necessary.
8. Internalleakage Excessive leakage will cause lower charge pressure
and affect performance. Install loop flushing defeat option and monitor case
flow. lf case flow is excessive, motor may require major
repair. Contact your Danfoss service provider.
Check Cause Corrective action
'l Oillevel Insufficient hydraulic fluid will cause overheating. Fill reservoir to proper level,
2. Heat exchanger Blocked heat exchanger or low air flow will not
sufficiently cool the system. Check temperature upstream and downstream of heat
exchanger. Clean, repair, or replace heat exchanger if
necessary.
3. Loop flushing charge pressure Inappropriately high loop flushing relief valve
setting will reduce or prevent loop flushing flow.
lmproper orifice size will not give proper flow for
cooling purposes.
Monitor case drain flow. lf low adjust loop flushing
relief valve setting or replace with orificed type relief.
4. System pressure lf system relief valve settings aretoo fow, excess
heat will be generated. Adjust system relief valve settings.
5. Air in system Entrained air generates heat under pressure and
causes cavitation Look for foam or bubbles in reservoir. Check for leak
on inlet side of charge pump.
6. Internalleakage Excessive internal leakage will overheat the system. Install loop flushing defeat option and monitor case
flow. lf case flow is excessive, motor may require major
repair. Contact your Danfoss service provider.
Check Cause, Corrective action
IOillevelin reservoir Insufficient hydraulic fluid will cause cavitation. Fill reservoir to proper level.
2. Air in system Air bubbles may lead to cavitation. OLookforfoam or bubbles in reservolr. Checkfor leak
on inlet side of charge pump.
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Service Manual Series 51 and 51-1 Motors Service Manual
Troubleshooting
Motor operates normally in one direction only
lmproper output speed
Low outputtorque
Check Cause Corrective action
3. Shaft coupling Loose shaft coupling creates excess noise. Replace loose shaft coupling. Replace or repair motor
if shaft splines are worn excessively.
4. Shaft alignment Misaligned shafts create excessive noise and
damage motor. Correct shaft misalignment.
Check Cause Corrective action
1Charge pressure lf charge pressure is low in one direction, the loop
flushing shuttle spool may be sticking to one side. Measure charge pressure in forward and reverse. lf
pressure drops in one direction, inspect and repair
loop flushing shuttle spool.
2, Motor control lf controlshifts motorto minimum displacement in
one direction, motor may not have enough torque
to operate.
Measure maximum and minimum servo pressures to
check control operation. Repair control or correct
input signal if necessary.
3. Pressure compensator control lf pressure compensator operates in one direction
only, the motor will stay at minimum displacement
in the otherdirection
Check brake pressure defeat spool. lt may be sticking
or receiving an improper signal. Repair spool or
correct input signal.
Check Cause Corrbctive action
1Oillevelin reservoir Insufficient hydraulic fluid will reduce system
efficiency. Fill reservoir to proper level.
2. Threshold setting lmproper threshold setting will cause motor to
have wrong displacement for given signal. Check th reshold setting. Refer to control service
manual for adjustment procedure.
3. P ressu re compensator setting lmproper pressure compensator setting shifts
motor displacement at wrong pressure. Check pressure compensator setting. Adjust if
necessary.
4. Controlspoolor piston Pressure compensator piston or spoolsticking
holds motor at wrong displacement. Check pressure compensator piston orspool. Repair
or replace if needed.
5. Controlorifices Blocked or restricted orifice causes motor to shift
improperly. Remove, inspect, and clean allorifices.
6. Control piston Sticliy control piston causes motorto shift
improperly. Check control piston for proper operation. Repair if
necessary.
7. Control input signal lmproper input signal causes motor to shift
improperly. Correct control input signal.
8. lnternal leakage Excess internal leakage causes lower charge
pressure and affects system performance including
output speed.
Install loopflushing defeat option and monitor case
flow- lf case flow is excessive, motor may require major
repair. Contact your Danfoss Service Provider.
Check Cause Corrective,action'
ISystem pressure Low system pressure at motor reduces output
torque. Measure system pressure at the motor. lf the pressure
limiter or relief valve setting is low, increase setting to
the proper level.
2. Charge pressure Low loop flushing relief valve setting may cause
improper supply pressure to motor control. Measure charge pressure in forward and reverse.
Adjust loop flushing relief valve setting if necessary.
3. Pressu re compensator setting High pressure compensator setting causes
improper motor displacement for torque required. check and adjust pressure compensator setting.
t 1 008557 . Rev BA . June 2014
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.-#jr".l4( li o s
;iexP
Service Manual Series 51 and 51-1 Motors Service Manual
Troubleshooting
Check Cause Corrective action
A
T. Control orifices Blocked or restricted orifice causes motor to shift
improperly. Remove, inspect and clean allorifices.
5. Pressure compensator piston or
spool Sticking pressure compensator piston or spool
causes controlto hold motor at minimum
displacement.
Remove and inspect control spool and sensing piston.
Repair or replace if necessary.
6- Controlspoolor piston Sticking 4-way spool or control piston causes
motor to shift improperly. Remove and inspect 4-way spool and control piston.
Repair or replace if necessary.
7. Two position solenoid Two position control not shifting motor to
maximum displacement. lnspect solenoid valve for bent stem or bad coil.
Repair or replace if necessary.
8. Control input signal lmproper control input signal causes motor to stay
at minimum displacement. Correct control input signal.
9. Threshold setting lmproper threshold setting causes improper motor
displacement for torque required. Check and adjust threshold setting.
10. Internal leakage Excess internal leakage causes charge pressure to
decay, reducing output torque. Install loop flushing defeat option and monitor case
flow. lf case flow is excessive, motor may require major
repair. Contact your Danfoss Service Provider.
1 1 008567 . Rev BA . June 201 431
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Service Manual Series 51 and 51-1 Motors Service Manual
Adjustments
Overview
...,fu Warninq
This service procedure may require disabiing the vehicle 1 machine (raising the wheels off the ground,
disconnectinq the worl< function, arrd so forth) wlrile performing, in order to prevent injury to the
technician anc.l bystanders. T..ike tlre necessary safety precautions
Adjust components of the Series 51 and Series 51-l motors perfollowing procedures (where necessary,
refer to Pressure measuremenfs on page 23, for gauge port locations and sizes):
Charge pressure relief valve
Set the charge pressure relief valve to the modelorder code specifications.In most applications, the
motorchargereliefvalveisset2to4bar [29to58psil belowthesettingofthepumpchargereliefvalve
(measured with the pump in its neutral or zero-angle position). This setting assumes a reservoir
temperature of 50" Cl'122'F]. Charge pressure is referenced {additive) to case pressure.
Measuring charge pressure
1. Install a 0 to 60 bar [0 to t 000 psil pressure gauge in port Ml or M2 (use which ever is at low loop
pressure).
2. Install a 0 to 60 bar [0 to t 000 psil gauge in port Ll or L2 to measure case pressure.
3. Operate the system with the prime mover at normal operating speed and the pump at half stroke
(forward or reverse).
Series 51 charge pressure relief valve
Adjustment
plug
"7 t
I l16
lock nut
i-*"1
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Older Series 5'l and Series 51-1 motors may be equipped with an externalscrew adjustable charge
pressure relief valve (not shown).
Adjusting charge pressure
"dh warning
Itrcorrect charge pressure setiings may resuit in the inability to build required system pressure and / or
inadequate loop flushinq flows. You must maintain ihe correct charge pressure uncler all operation
conditions to maintain pump performance
1. Loosen the lock nut using a 11/16 hex wrench.
2, Turn the adjustment plug with a large screwdriverar l3mm hex wrench.
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Service Manual Series 51 and 51-I Motors Service Manual
Adjustments
Minimum displacement limiter
Clockwise rotation of the plug increases the setting, and counterclockwise rotation decreases the
setting. The charge pressure setting will be reduced or increased at a rate of approximately 3.4 bar [50
psil per turn.
3. After adjusting the plug, torque the locknut to 52 N.m [38 lbf.ft]. Do not overtorque
4. Removethegauges.
5. Reinstallthe port plugs.
Motors with loop flushing defeated, or equipped with an orificed charge pressure relief valve (see
Charge relief valve on page 44) do not require adjustment.
Series 51-l charge pressure relief valve
.fu Warnlng
Adjustment of the minimum dispiacement limiter can result in undesirable or unsafe speed contjitions.
Consult'with the Original Equipment Manufacturer or your Danfoss representative before chapging the
minimum displacement setting. After adjustment, rrerifv minimunr displacement settinq bv using an
appropriate test apparatus.
The factory sets minimum displacement. A tamper-resistant cap covers the adjustment screw.
lffi Caurion
I o avoid unexpected changes in operating ccnditioris and to prevent external lealcage, torque the lock
irut {Y20) after everv adiustment.
Detect changes in motor displacement by providing a constant flow of fluid to the motor, while
maintaining the motor at minimum displacement and monitoring the motor output shaft speed. An
increase in displacement will result in a decrease in shaft speed, while a decrease in displacement will
result in an increase in shaft speed.
Adjustin g minimum displacement
1. Remove the tamper resistant cap (e120) from the adjusting screw (ylO). Removing the tamper
resistant cap destroys the locking device.
2. Discard the cap (Qt zO1 after comparing it with a new one to make sure the new one fits.
ffi ttl,u inch
52 Nm [38lbf'ftl
Adjustment plug
1 1008567 . Rev BA. June 2014 33
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Service Manual Series 51-1 Controls 81 ,B.2,B7,El,EZ,El,FI, F2, N1, T1,T2,T7,TA,TH,p7,pg
T1 ,T2,T7,T A, TH Pressure Compensator (PC) controls
Schematic diagrams - Tl /72/f7
Schematic diagrams-TH
(R5 shown)
Adjustment
$ warning
T1t2t7 C2
Do not perform tlris prccedure unless the machine can be safely operaied wfiile loading the motor shaft
as described. lf trecessary, remove the motor frorn the application and perform this procedure in an
a ppropriate test stand.
PC start pressure
The pressure compensator start pressure setting is adjustable in a range from 1 10 to 370 bar [15g5 to
5366 psil. To measure the start pressure setting:
. applythe vehicle's brakes to lock the motor shaft from turning
or
. add an elrtreme load to the workfunction of the machine.
To check or reset the pressure compensator setting on a vehicre:
t. lnstall a 600 bar [10,000 psi] gauge at port M4 to monitor pressure at the rod end (maximum
displacement) of the servo piston.
Due to the controf's configuration the pressure at M4 will equal the system pressure.
2, Install a 600 bar [10,000 psi] gauge at port M3 to monitor pressure at the piston end (minimum
displacement)of the servo piston.
| 1009443 . Rev BA . February 201 5
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Service Manual Series 51-1 Controls 81, B,2,B7,EI,EZ,ET,Fl, F2, Nl, T7,T2,T7,TA,TH, pZ, pg
T1,T2,T7,T A,TH Pressure Compensator (PC) controls
3. Start the prime mover and operate at normal speed.
4' Stroke pump very slowly to gradually increase system pressure to the PC setting pressure, or:
a) lower the pump's multifunction valve (series 90) or HPRV (H1) below the pC setting
b) stroke the pump to approximately 1/4 displacement
c) adjust the multifunction valve (Series 90) or HPRV (Ht ) to slowly increase system pressure to the
PC setting pressure.
5. Watch the gauge at port M3. When pressure in M3 begins to decrease, note the pressure at port M4.
This is the PC setting.
lf you don't get the correct pressure setting, repeat step 4 using a different option. The result
depends on the application.
PC setting
M4
To check or reset the pressure compensator setting on a test stand:
1. Monitor system flow.
2. Increase the system pressure until flow begins to increase. System gauge pressure at this point is the
PC setting. \
To adjust the pressure compensator setting:
1. Use a 1Omm hex wrench to loosen the seal locknut.
2. Using a 3mm internal hexwrench, turn the PC adjusting screw clockwise to increase the pressure
setting, counter-clockwise to decrease the setting.
The pressure compensator setting changes at a rate of approximiiety-o r-ar taoO ptif per turn
Using a 1Omm hex wrench to hold the adjustment screw in place torque the seal locknut to 52 N.m
t38lbf.ftl.
Recheck the pressure compensator setting and readjust the as necessary.
3.
4.
1 1009443 . Rev BA . February 201 5
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