Skytron 1700 User manual

Page 33
SURGICAL TABLE
MODEL 1700
MAINTENANCE MANUAL

Page 27
SECTION I HYDRAULIC SYSTEM........................................................................................................ 1
1-1. General........................................................................................................................................... 1
1-2. Component Operation .................................................................................................................... 2
a. Motor/Pump Operation ............................................................................................................. 2
b. Pressure Relief Valve............................................................................................................... 2
c. Mini-Valves............................................................................................................................... 3
d. Mini-valve in Neutral Position ................................................................................................... 3
e. Mini-Valve Right Port Activated ................................................................................................ 4
f. Mini-Valve Left Port Activated .................................................................................................. 4
g. Hydraulic Cylinders (Slave Cylinders) ...................................................................................... 5
h. Elevation Cylinder Return Circuit.............................................................................................. 6
i. Brake System ........................................................................................................................... 7
j. Emergency Brake Release....................................................................................................... 7
1-3. Hydraulic Adjustments.................................................................................................................... 8
a. Fluid Level. ............................................................................................................................... 8
b. Bleeding The Hydraulic System ............................................................................................... 8
c. Pressure Relief Valve............................................................................................................... 8
d. Speed Controls......................................................................................................................... 9
SECTION II HYDRAULIC TROUBLESHOOTING................................................................................ 10
2-1. Precautions .................................................................................................................................. 10
2-2. Troubleshooting Notes ................................................................................................................. 10
2-3. ELEVATION DIAGNOSIS CHART ............................................................................................... 11
2-4. TRENDELENBURG DIAGNOSIS CHART ................................................................................... 12
2-5. LATERAL - TILT DIAGNOSIS CHART......................................................................................... 13
2-6. BACK SECTION DIAGNOSIS CHART ......................................................................................... 14
2-7. LEG SECTION DIAGNOSIS CHART ............................................................................................ 15
2-8. BRAKE CIRCUIT DIAGNOSIS CHART ...................................................................................... 16
2-9. Flexible Hose Identification and Placement.................................................................................. 17
SECTION III ELECTRICAL SYSTEM .................................................................................................. 18
3-1. General......................................................................................................................................... 18
3-2. Components ................................................................................................................................. 18
SECTION IV ELECTRICAL SYSTEM TROUBLESHOOTING .............................................................. 20
4-1. Troubleshooting Notes ................................................................................................................. 20
4-2. Main Switch .................................................................................................................................. 20
4-3. Pendant Control ........................................................................................................................... 21
4-4. Relay Box ..................................................................................................................................... 21
4-5. Solenoids...................................................................................................................................... 22
4-6. Motor/Pump Assembly ................................................................................................................. 25
Although current at time of publication, SKYTRON's policy of continuous development makes this manual
subject to change without notice. 9/03
Table of Contents
WARNING
Indicatesapossibilityofpersonalinjury.
CAUTION
Indicates a possibility of damage to
equipment.
NOTE
Indicatesimportantfactsorhelpfulhints.

Page 29
BASIC RECOMMENDED TOOLS:
1/8". 1/4" STRAIGHT BLADE SCREWDRIVERS
#2 PHILLIPS SCREWDRIVER
HYDRAULIC PRESSURE GAUGE SKYTRON P.N. 6-050-02
METRIC ALLEN® WRENCHES 1.5mm-8mm
ADJUSTABLE CRESCENT WRENCH
DIGITAL VOLTMETER, TRUE RMS
METRIC OPEN END WRENCHES 7mm-18mm
BASIC RECOMMENDED MAINTENANCE PROCEDURES
The basic items notes below should be inspected at a minimal interval period of 6 months (dependant on
usage). For optimal usage, safety and longevity of the product, have it serviced only by an authorized
Skytron representative with authentic Skytron replacement parts.
• Check Power Cord (if applicable)
• Check Pendant Control (if applicable)
• Check Oil Level in Reservoir
• Check For Hydraulic Leaks
• Check Pressure Relief Valve Setting
• Check All Table Functions
• Check Side Rails
• Check Velcro
• Lubricate Elevation Slider Assembly with SKYTRON Slider Grease P/N D6-010-89
• Tighten X-Ray Top Stand-Offs, Use Loc-tite
• Lubricate Castors
• Check brake pads for wear and inspect brake cylinders for proper operation.
Only facility-authorized SKYTRON trained, maintenance personnel should troubleshoot the
SKYTRON Surgical Table. Trouble shooting by unauthorized personnel could result in
personal injury or equipment damage.
How to contact us:
Skytron
5000 36th St. SE, Grand Rapids, MI 49512
PH: 1-800-759-8766 (SKY-TRON)
FAX: [phone]

Page 30
IPX4 ENCLOSURE CLASS
VVOLTAGE RATING OF THE UNIT
AAMPERAGE RATING OF THE UNIT
HZ FREQUENCY OF THE UNIT
INDICATES DANGEROUS VOLTAGE, 120 V, 60 Hz
PROTECTIVE GROUNDING.
IN ORDER TO ENSURE PROPER GROUNDING RELIABILITY,
THIS TABLE MUST BE CONNECTED TO A PROPERLY GROUNDED
HOSPITAL GRADE OUTLET.
CONNECTION FOR NEUTRAL CONDUCTOR SUPPLIED
N
UNIT TO BE USED ONLY IN SPECIFIED ENVIRONMENTAL CONDITIONS
TEMPERATURE: 15˚ - 30˚ C (60˚ -85˚ F)
HUMIDITY: 30% - 60% RELATIVE HUMIDITY, NON CONDENSING
AC VOLTAGE
CLASS I DEFIBRILLATION PROOF, TYPE B EQUIPMENT- IPX4 RATED.
INTERNALLY POWERED EQUIPMENT
TYPE B
EQUIPMENT
EQUIPMENT LABELS AND SPECIFICATIONS
ATTENTION, CONSULT MANUAL FOR FURTHER INSTRUCTIONS.
INDICATES SPECIAL USER ATTENTION.
POWERED BY AC VOLTAGE
FUSE (2) 10 AMP FAST ACTING
10A

Page 31
1700 Series General Purpose Surgical Table Specifications
TOP VIEW
SIDEVIEW ENDVIEW
90˚
60˚
9-1/2" 22" 21-1/2" 22"
14-1/2"
76"
8-3/4"
35-1/2" 19"
22"
19-3/4"
39" Max
29" Min
Electrical Specifications
Power requirements
Current Leakage
Power Cord
ENTELA CERTIFIED
TO UL2601-1
CAN/CSA601.1, IEC 60601-2-46
120 VAC, 60Hz, 300 Watts
Less than 100 micro amps
15 feet w/hospital grade connector(removeable)

Page 1
LEG
SECTION
CLEAR
PLASTIC
LINE
EMERGENCY
BRAKE
RELEASE
BRAKE SYSTEM
BACK
SECTION
TREND
ELEVATION
PRESSURE
RELIEFVALVE
3
5
9
8
7
6
4
2
1
98
7
654321
9
8
7
6
5
4
3
2
110
LATERAL
TILT
MOTOR/PUMP
ASSEMBLY
MINI-VALVES
RESERVOIR
1-1. General
Electro-Hydraulic System
The hydraulic system (with the exception of the
hydraulic cylinders and hoses) is contained within
the base of the table. The hydraulic valves and
pump are electrically controlled by the use of a
hand-heldpushbuttonpendantcontrol. Thepower
requirementsfor thetable are120 VAC,5 amp,60
Hz.
The table contains the following components. Re-
fertotheblockdiagram(figure1-1)forrelationship.
a. Oil Reservoir - Main oil supply. Approximately
two quarts.
b. Motor/Pump Assembly - A positive displace-
ment gear type pump provides the necessary oil
pressure and volume.
c. PressureReliefValve-Providesanalternateoil
pathwhen thehydrauliccylinders reachtheend of
their stroke.
d. Electro/Hydraulic Mini-Valve Assemblies -These
directthefluidtotheappropriate hydrauliccylinders.
e. Hydraulic Lines, Fittings, Connections - They
provide a path for the hydraulic oil.
f. HydraulicCylinders-Theyconvertthehydraulic
fluidpressureandvolumeintomechanicalmotion.
SECTION I HYDRAULIC SYSTEM
Figure 1-1. Hydraulic Block Diagram

Page 2
1-2. Component Operation
a. Motor/Pump Operation
The motor/pump assembly is a positive displace-
mentgeartypepumpthatprovidestheoilpressure
and volume for the entire hydraulic system. The
pumphasaninletsideandanoutletside. Theinlet
side is connected to the reservoir which provides
the oil supply.
The output line of the pump is connected to the
main oil galley which is internal and common to all
thehydraulicmini-valvesandpressurereliefvalve.
Also, common to the hydraulic mini-valves and
pressure relief valve is an oil galley that internally
connectstotheoilreservoirtoprovideareturnpath
for the hydraulic oil. See figure 1-2.
Figure 1-4. Pressure Relief Valve Functioning
Figure 1-3. Pressure Relief Valve Not
Functioning
b. Pressure Relief Valve
Thisdeviceprovidesanalternateoilpathwhenthe
hydraulic cylinders reach the end of their stroke
andthepumpcontinuestorun. Ifthispathwerenot
provided, the pump motor would stall because the
oil cannot be compressed. The pressure relief
valveisdirectlyconnectedtothemini-valvebodies
and shares both the common internal main pres-
sure oil galley, and the return oil galley, that inter-
nally connect to the reservoir. See figure 1-3.
Figure 1-2.
The main component of the valve is an adjustable
spring loaded plunger that is pushed off from its
seatbytheoilpressure. Theoilthenflowsbackinto
the reservoir. See figure 1-4. Turning the adjust-
ment nut clockwise increases the amount of oil
pressure required to open the valve, and turning it
counterclockwisedecreasestheamountofoilpres-
sure. (See adjustment section for specification.)
PRESSURE RELIEF
ADJUSTMENT NUT
SPRING LOADED
PLUNGER
PRESSURE
GAUGE
PRESSURE RELIEF
ADJUSTMENT NUT
SPRING LOADED
PLUNGER
PRESSURE
GAUGE
MINI-VALVES
PRESSURE
RELIFVALVE
PUMP
OUTLET
PUMP
INLET
MAIN RETURN
OIL GALLEY
(INTERNAL)
MAIN PRESSURE
OIL GALLEY
(INTERNAL)
MOTOR/
PUMP
ASSEMBLY OIL
RESERVOIR

Page 3
c. Mini-Valves
The operation of the mini-valves is identical for all
table functions except the elevation and brake
circuits. These two hydraulic circuits use a 3-way
(singlecheckvalve)typemini-valve.Allotherfunc-
tions use a 4-way (dual check valve) type mini-
valve.
Either type mini-valve is controlled by two pushing
type, electrically operated solenoids. The sole-
noids push the spool valve (located in the lower
portion of the valve) one way or the other. This
motion opens the main supply galley (which has
pumppressure) allowingthe oiltoflow throughthe
variousparts ofthemini-valve tothe function. The
spool valve also opens an oil return circuit which
allows the oil to return to the oil reservoir.
The main components of the mini-valve and their
functions are listed below:
1. Spool Valve - Opens the main oil galley
(pump pressure) to either mini-valve outlet de-
pending on which direction the spool valve is
pushed. Also it provides a return path for the oil
returning back into the reservoir.
2. Pilot Plunger - There are two plungers in a
four-way mini-valve (one in a 3-way mini-valve),
one under each check valve. The purpose of the
pilot plungers is to mechanically open the return
check valve allowing the oil to return back into the
reservoir.
3. CheckValve-Twoareprovidedineachfour-
waymini-valvetosealtheoilinthecylindersandoil
linesand preventanymovement ofthe table. One
check valve is provided in a 3-way mini-valve.
4. Speed Adjustments - There are two speed
adjustments in each mini-valve. They are needle
valve type controls which restrict the volume of oil
returning back into the reservoir, thereby control-
lingthespeedofthetablesurfacemovement. A3-
way mini-valve has only one speed adjustment.
Thespeedcontrolsarealwayslocatedinthereturn
oilcircuit. Thispreventsuncontrolledmovementof
thepistonintheslavecylinderduetoonesideofthe
piston being loaded with hydraulic pressure and
the other side having no load.
Also,byusingthiscontrolmethod,itdoesn’tmatter
what size cylinder and piston is used because the
speedcanbecontrolledbyrestrictingthereturnoil.
Ifthepumpputsoutmorevolumetoacertainslave
cylinder than the speed control is allowing to go
back to the reservoir, the pressure relief valve
provides an alternate path for the pump oil.
d. Mini-Valve in Neutral Position
(No fluid flow) See figure 1-5.
1. Spool Valve Centered - This closes off both
oil pressure and oil return galleys.
2. PilotPlungersBothClosed-Thepilotplung-
ers control the opening of the check valves. If they
are closed, the check valves must be closed.
3. CheckValves-Bothcheckvalvesareclosed
trapping the oil in the cylinder and oil lines.
4. Speed Adjustment - When the mini-valve is
in the neutral position, the speed adjustment does
notaffectanythingbecausethereisnotanyoilflow.
Figure 1-5. Mini-Valve in Neutral Position
OIL RETURN
(RETURN)
OIL GALLERY
(PRESSURE) SPOOL VALVE SOLENOID PISTON
PILOT
PLUNGER
CHECK
VALVE
SPEED
CONTROL
BALL
VALVE OIL LINEOIL LINE

Page 4
e. Mini-Valve Right Port Activated
(See figure 1-6)
Slave Cylinder Piston Moves to Left
Right Mini-Valve Port is Supply Line
Left Mini-Valve Port is Return Line
f. Mini-Valve Left Port Activated
(See figure 1-7.)
Slave Cylinder Piston Moves to Right
Left Mini-Valve Port is Supply Line
Right Mini-Valve Port is Return Line
1. Spool Valve - Pushed to the left by electric
solenoid. This opens the internal oil pressure gal-
ley allowing the fluid to go through the check valve
andontothecylinder. Also, thespoolvalveopens
the oil return line providing an oil path through the
internal oil galley back to the reservoir.
2. PilotPlunger Valve- Leftpilotplungervalve
ispushedupbytheincomingoilpressuremechani-
callyopeningthecheckvalvelocatedaboveitinthe
returncircuit. Thisactionallowstheoilfromtheleft
side of the slave cylinder to go back into the
reservoir. The right pilot plunger valve is not
affected in this operation mode.
3. Check Valves - Both check valves are
opened in this operation mode. The right check
valveispushedopenbytheoilpressurecreatedby
thepump. Theoilthencontinuestogothrough the
lines and pushes the slave cylinder piston to the
left. At the same time, the left check valve is held
open mechanically by the pilot plunger providing a
returnpathfortheoilthroughthemini-valveback
to the reservoir.
4. SpeedAdjustment-Therightspeed control
(output side) does not have any effect in this
operation mode because the oil is routed around
thespeedadjustment throughaby-passvalve and
then to the output port. The left speed adjustment
controls the speed of the table function by restrict-
ing the amount of oil going back into the reservoir.
1. Spool Valve -Pushed to the right by electric
solenoid.Thisopenstheinternaloilpressuregalley
allowingthefluidtogothroughthecheckvalveand
onto thecylinder. Also, thespool valveopensthe
oil return line providing an oil path through the
internal oil galley back to the reservoir.
2. PilotPlunger Valve-Right pilotplungervalve
ispushedupbytheincomingoilpressuremechani-
callyopeningthecheckvalvelocatedaboveitinthe
return circuit. This action allows the oil from the
right side of the slave cylinder to go back into the
reservoir. Theleftpilotplungervalveisnotaffected
in this operation mode.
3. CheckValves-Bothcheckvalvesareopened
in this operation mode. The left valve is pushed
openbytheoilpressurecreatedbythepump. The
oil then continues to go through the lines and
pushestheslavecylinderpistontotheright. Atthe
same time, the right check valve is held open
mechanicallybythepilotplungerprovidingareturn
pathfortheoil throughthemini-valve backtothe
reservoir.
4. Speed Adjustment - The left speed control
(output side) does not have any effect in this oper-
ation mode because the oil is routed around the
speed adjustment through a by-pass valve and
thentotheoutputport. Therightspeedadjustment
controls the speed of the table function by restrict-
ing the amount of oil going back to the reservoir.
Figure 1-6. Mini-Valve Right Port Activated Figure 1-7. Mini-Valve Left Port Activated
INLET OUTLET
INLET
OUTLET

Page 5
PISTON
RAM
2. Trendelenburg Cylinder Assembly - The
Trendelenburg and Lateral Tilt cylinders share a
common housing. The Trendelenburg assembly
consists of two pistons and connecting rods that
connect to a stationary pin on the Trendelenburg
pivot casting which is attached to the center col-
umn. The cylinder housing is attached to the table
top and connects to the pivot casting with an axis
pin. When hydraulic fluid is pumped into one
cylinder, the cylinder housing itself moves around
the pivot housing causing the table top to tilt. A
return path is opened for the hydraulic fluid of the
other piston. See figure 1-10.
g. Hydraulic Cylinders (Slave Cylinders)
Thereareseveraldifferenttypesofhydrauliccylin-
ders used in the table that activate the control
functions,all operatebasically thesameway. The
controlfunctionsarelistedbelow:(Seefigure1-8.).
Back Section--1, double action cylinder
Leg Section--1, double action cylinder
Trendelenburg--2, single action cylinders func-
tioning together to act as 1 dual action cylinder
Lateral Tilt--2, single action cylinders func-
tioning together to act as 1 dual action cylinder
Elevation--1, single action cylinder
Brakes--4, single action cylinders
Figure 1-8. Cylinder Placement
1. BackSectionandLegSectionCylinders-The
double action cylinders are closed at one end and
have a movable piston with hydraulic fluid on both
sides.Connectedtothispistonisaramthatexitsout
ofthe otherend ofthecylinder.Through theuse ofa
clevisand pinarrangement, thisramis connectedto
a movable table surface.
Themovablesurfacecanbe moved one way orthe
other by pumping hydraulic fluid into the cylinder on
either side of the piston. A return path is opened for
the oil on the other side. See figure 1-9.
Figure 1-10. Trendelenburg Cylinder Assy.
3. Lateral Tilt Assembly - The lateral tilt assembly
consists of two pistons and connecting rods. The
connecting rods attach to the table top frame.
When hydraulic fluid is pumped into one cylinder,
the piston and connecting rod tilts the table top to
one side. To tilt the table top in the opposite
direction,fluidispumpedintotheoppositecylinder.
See figure 1-11.
Figure 1-9. Back Section Cylinder Figure 1-11. Lateral Tilt Cylinder Assembly
BACK
SECTION
LEG
SECTION
ELEVATION
TRENDELENBURG
LATERAL
TILT
PIN
(STATIONARY)
CONNECTING
RODS
PISTON
PISTON
PISTON
PISTON
CONNECTING
RODS

Page 6
4. ElevationCylinder -Thissingle actioncylin-
der does not have hydraulic fluid on both sides of
thepiston.Itdependsontheweightofthetabletop
assembly to lower it.
The cylinder is set in the center of the elevation
maincolumn. Thecylinderiselevatedbythedriven
forceoftheoilpressure. Whenlowering,theoilthat
is accumulated in the cylinder is returned to the oil
reservoirthroughthemini-valveduetothetabletop
weight.
A slider support assembly is used to support the
weightofthe uppertable section. Astainless steel
shroud covers the flexible hydraulic hoses and
slider. See figure 1-12.
Figure 1-12. Elevation Cylinder Assembly
5. Brake Cylinders - The brake cylinders are
single action type similar to the elevation cylinder.
The movable piston's ram is connected to a brake
pad. Seefigure1-13. Oilpumpedintothetopofthe
cylinder pushes the piston down raising the table
baseoffitscasters. Aninternalreturnspringonthe
bottomofthepiston,pushesthepistonuptoreturn
the oil through the mini-valve to the reservoir.
Figure 1-13. Single Action Brake Cylinder
h. Elevation Cylinder Return Circuit
Three-way (single check valve type) mini-valves
control both the elevation and return circuits. The
elevation circuit operation within the mini-valve is
identical to the operation of the four-way valves
previously described. In the return position, inlet
pressurepushesthepilotplungerupandopensthe
return check valve. See figure 1-14. The open
checkvalveallows apathfortheoilintheelevation
cylinder to return to the reservoir. When the pilot
plungervalveisopened,thecontinuingpump pres-
sure opens the pressure relief valve which pro-
vides a return oil path to the reservoir.
Themini-valvecontainsonlyonecheckvalve which
is used to trap the oil in the elevation cylinder
thereby supporting the table top. When the top is
loweredthecheckvalveismechanicallyheldopen
by the pilot plunger through pump pressure.
Figure 1-14. Elevation Return Circuit
INLET
RETURNTO
RESERVOIR
TO RESERVOIR
THROUGH
PRESSURE
RELIEFVALVE
ELEVATION
CYLINDER
EXTERIOR
SHROUD
SLIDER
SUPPORT
ASSEMBLY PISTON
BRAKE
PAD
RETURN
SPRING
PISTON
OIL LINE

Page 7
i. Brake System
Thebrakesystemconsistsofthefollowingcompo-
nents: (figure 1-15)
1. Single action slave cylinders (4 each).
2. 3-way (single check valve type) mini-valve.
3. Manually controlled emergency brake re-
lease.
4. Plumbing terminal, flexible hoses, copper
lines and "O" rings.
5. Portions of the electrical system.
Each corner of the cast-iron table base has a
hydraulic brake cylinder. These single action cyl-
indersarehydraulicallyconnectedinparalleltothe
mini-valve and all four are activated together. It is
normalforonecornerofthetabletoraisebeforethe
others due to the weight distribution of the table.
An electronic timer in the relay box is activated
when any function on the pendant control is
pushed momentarily. The pump/motorandbrake
system mini-valve are activated and the brake
cylinders are completely set. The electronic timer
runs for approx. 8-10 seconds.
The brakes are released by pushing the BRAKE
UNLOCK button momentarily. An electronic timer
in the relay box activates the brake function hy-
draulic mini-valve and pump/motor.
When activated, the return hydraulic circuit oper-
ates similar to the elevation cylinder return circuit.
Returnspringsinside thesingle actionbrake cylin-
ders retract the brake pads and provide the pres-
suretoreturnthehydraulicoilbacktothereservoir.
The electronic timer operates the return circuit for
approximately 8-10 seconds.
j. Emergency Brake Release
Theemergencybrakereleaseissimplyamanually
operatedbypass valveconnected inparalleltothe
brakecylinders andtheoilreservoir. Seefigure 1-
16. When the valve is opened (turned counter-
clockwise) a return circuit for the brake hydraulic
fluid is opened. The return springs force the
pistons up pushing the hydraulic oil back into the
reservoir and retracting the brake pads.
Figure 1-15. Brake System Block Diagram
Figure 1-16.
NOTE
•The emergency brake release valve
mustbetightenedsecurelywhennotin
use.
•If the emergency brake release valve
has been operated, the UNLOCK but-
tonon thependantcontrol mayhaveto
bepressedbeforebrakeswilllockagain.
If the emergency brake release valve is open or
loose,thebrakeswillreleaseslowly-dependingon
how loose the valve is, this could take anywhere
from a few minutes to several hours.
EMERGENCY
BRAKE RELEASE
RELIEF
VALVE
PLUMBING
TERMINAL
BRAKE
BRAKE SYSTEM
PUMP/MOTOR
ASSEMBLY
BRAKE
CYLINDERS

Page 8
Figure 1-18.
2. Raise the table top until the piston reaches
theendofitsstrokeandstalls. Observe readingon
pressuregaugeandturntheadjustmentnut(clock-
wisetoincrease oil pressure, counterclockwise to
decrease) until desired reading is obtained. Pres-
sure should be 80KG/CM† -1138 PSI.
Figure 1-17.
ThetypeofoilthatshouldbeusedisMobilDTE#25
or equivalent. This is a very high quality hydraulic
oil. The table requires approximately two quarts of
oil to operate properly.
b. Bleeding The Hydraulic System
Topurgetheairfromthehydraulicsystem,operate
each function back and forth at least two or three
times.
NOTE
Whenever a hydraulic line or compo-
nentisreplaced,bleedtheairoutofthe
lines using the pump pressure before
making the final connection. Then op-
erate the function until it stalls in both
directions.
1-3. Hydraulic Adjustments
a. Fluid Level.
Thefluidlevelshouldbe approximately1/2" below
thefiller holeorgasket surface.Ifadditionalfluid is
needed, remove the filler vent cap with a phillips
screwdriver and add fluid through this opening
using a funnel. See figure 1-17.
NOTE
The elevation cylinder should be com-
pletely down and all the other control
functions in their neutral position when
checking oil level.
c. Pressure Relief Valve
Thepressure reliefvalve isadjustedby turningthe
adjustmentnutuntilthedesiredpressureisreached.
To adjust:
1. Removetheblindcapandattachahydraulic
pressuregauge tothemainoilgalleyusinga 6mm
plumbing bolt. See figure 1-18.
PRESSURE
GAUGE
PRESSURE
RELIEF VALVE
ATTACH
HERE
BACK VIEW OF
RELIEF VALVE
FILLER CAP
FILLER FITTING
GASKET

Page 9
Figure 1-19.
Any control function should move in either direc-
tionatthesamerate. Iftherateofacertainfunction
is too slow, open the speed control slightly and
recheck. Usethesecondhandonawatchandtime
a particular function. Match that time in the oppo-
site direction by opening or closing the speed
control. Approximate operating times are as fol-
lows:
Lateral Tilt 5 seconds
Back Up 13 seconds
Back Down 5 seconds
d. Speed Controls
Thespeedcontrolsrestrictthevolumeofoilreturn-
ing back to the reservoir thereby controlling the
speed of each control function.
All four-way mini-valves, have two speed controls
located in the ends of each valve body. All three-
way mini-valves have only one speed control.
One speed control adjusts one direction of a
particular function and the opposite speed control
adjuststheotherdirection. They areadjustableby
using a small straight blade screwdriver and
turning the adjustment screw clockwise to de-
crease the speed and counterclockwise to
increase the speed. Refer to figure 1-19.
LEG UP
BRAKE
LEG DOWN
BACK UP
TILT RIGHT
TREND
BACK
DOWN
TILT
LEFT
REVTREND
TABLE DOWN
Apressure gaugeshouldbeusedtosetthespeed
of the back section and Trendelenburg control
functions.
To adjust:
1. Attachthepressuregaugeontothe main oil
galley as shown in figure 1-19.
2. Thegaugeshouldread the following values
when operating the various control functions in
either direction. Turn the speed controls until
desired values are obtained.
Back Section Up 70KG/CM†-995PSI
Dn 70KG/CM†-995PSI
Trendelenburg Up 70KG/CM†-995PSI
Dn 70KG/CM†-995PSI
Elevation - There is not a speed adjustment for
raisingthe table. Thespeedcontrol willonlyaffect
the rate of descent and it should equal the rate of
elevation.

Page 10
SECTION II HYDRAULIC TROUBLESHOOTING
2-1. Precautions
Before attempting to troubleshoot any hydraulic
problemon thetable, pleaseread throughthe pre-
cautions and notes below.
CAUTION
Whendisconnectinganyofthehydrau-
lic lines, fittings, joints, hoses, etc., for
the following control functions, be sure
these table surfaces are in their down
position or completely supported.
•Elevation
•Back Section
•Leg Section
When working on the Trendelenburg
or lateral tilt hydraulic circuits, be sure
tosupportthetable top. Whenworking
on the brake system make sure the
brakes are completely retracted.
WARNING
Failuretofollowtheseprecautionsmay
result in an uncontrolled oil spray and
damage to the table or personal injury.
2-2. Troubleshooting Notes
When troubleshooting a table malfunction, first
determine the following:
1. Does the problem affect all control func-
tions?
2. Does the problem affect only one control
function?
3. Ifthe problemaffects onecontrol functionis
it in both directions?
4. Is the problem intermittent?
5. Is the problem no movement of a table
surface or does the table surface lose position?
Oncethe problem has been determined, concen-
trate on that particular hydraulic circuit or control
function.
Listed below are the hydraulic components that
are common with all hydraulic circuits. If there is a
problem with any of them, it could affect all control
functions.
1. Motor/Pump Assembly
2. Reservoir
3. Pressure Relief Valve
4. Certain Oil Lines and Galleys
Iftherewasaprobleminthefollowingcomponents,
only one control function would normally be af-
fected.
1. Mini-Valve
2. Slave Cylinder
3. Oil Lines
NOTE
Whenever a hydraulic line or compo-
nentisreplaced,bleedtheairoutofthe
lines using the pump pressure before
making the final connection. After all
connections are tight, cycle the control
function back and forth two or three
times to purge the remaining air from
the system.
CAUTION
When installing new "O" rings use white
lithiumgreaseorhydraulicoiltothoroughly
lubricate the "O" rings and cylinder. Keep
everything clean.
Each complete oil circuit is shown on the following
pages. Whentroubleshootingaparticularfunction,
refer to the appropriate oil circuit diagram and the
list of possible problems

Page 11
Problem
Table will not elevate properly Reason
Pressure Relief Valve Not Set Properly
Low on Oil
Spool Valve Not Centered
Defective Pump
Defective Mini-Valve
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
Incorrect Speed Adjustment
Bad Check Valve
Spool Valve Not Centered
Galled Slider Assembly
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
Table will not descend properly
2-3. ELEVATION DIAGNOSIS CHART
Bad Check Valve
Leaking Mini-Valve
Loose Fittings, Joints, Hoses
Leaking "O" Ring Inside Cylinder
Table loses elevation
Figure 2-1. Elevation Circuit
CYLINDER
BASE O-RING
PISTON
O-RING
CYLINDER
BASE
FLEXIBLE HOSE
PLUMBING
TERMINAL
COPPER
LINE
SPEED CONTROL
CHECKVALVE
ELEVATION
MINIVALVE

Page 12
Reason
Incorrect Speed Adjustment
Spool Valve Not Centered
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Bad Solenoid or Wiring
Defective Relay Box or Pendant Control
Problem
Trendelenburg function moves improperly
Trendelenburg function chatters or loses position
2-4. TRENDELENBURG DIAGNOSIS CHART
Defective or Dirty Check Valve
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
Figure 2-2. Trendelenburg Circuit
MAIN PLUMING
TERMINAL
SPEED CONTROL
CHECKVALVE
MINIVALVE
COPPER
LINES
PISTON
O-RING
CYLINDER
CAP O-RING

Page 13
Problem
Lateral tilt function moves improperly Reason Incorrect Speed Adjustment
Spool Valve Not Centered
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Bad Solenoid
Defective Relay Box or Pendant Control
Lateral tilt function chatters or loses position Defective or Dirty Check Valves
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
2-5. LATERAL TILT DIAGNOSIS CHART
Figure 2-3. Lateral Tilt Circuit
SPEED CONTROL
CHECKVALVE
MINIVALVE
PISTON
O-RING

Page 14
Figure 2-4. Back Section Circuit
2-6. BACK SECTION DIAGNOSIS CHART
Reason
Incorrect Speed Adjustment
Spool Valve Not Centered
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Bad Solenoid
Defective Relay Box or Pendant Control
Problem
Back Section function moves improperly
Defective or Dirty Check Valves
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
Back Section function chatters or loses position
SPEED CONTROL
CHECKVALVE
MINIVALVE
MAIN PLUMING
TERMINAL
COPPER
LINES

Page 15
2-7. LEG SECTION DIAGNOSIS CHART
Reason
Incorrect Speed Adjustment
Spool Valve Not Centered
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Bad Solenoid
Defective Relay Box or Pendant Control
Problem
Leg function moves improperly
Defective or Dirty Check Valves
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
Leg function chatters or loses position
Figure 2-5. Leg Section Circuit
SPEED CONTROL
CHECKVALVE
MINIVALVE
MAIN PLUMING
TERMINAL
COPPER
LINES