Midmark 647 Service And Parts Manual
Barrier-Free® Podiatry
Style B
Procedures Chair
Model Numbers:
647
Service and
Parts Manual
FOR USE BY MIDMARK TRAINED TECHNICIANS ONLY
Part No. 004-0579-00 Rev. 1/5/2018
Table of ContentsTable of Contents
GENERAL INFORMATION
Symbols ....................................... iii
Ordering Parts ............................. iii
Serial Number Location ............... iii
Specications ..............................iv
Model Identication /
Compliance Chart .......................v
Scheduled Maintenance /
General InfoSection A
Cleaning Chart ...........................vi
ACCESS PROCEDURES
PC Board Cover:
Standard Base ........................C-2
Rotational Base ......................C-3
Base Shrouds:
Raising (w/ bungee cord) ........C-4
Lower / Remove / Install .........C-5
Section CSection DDigitally Linked Files
Upholstery ................................C-6
Foot Extension Covers..............C-7
Foot Slide Remove / Install .......C-9
TROUBLESHOOTING
Troubleshooting Chart ..............A-2
Power to the Chair:
Standard Base ...................... A-10
Rotational Base ....................A-12
Base Up / Down ......................A-14
Back Up / Down ...................... A-16
Tilt Up / Down .........................A-18
Crash Avoidance System .......A-20
Position Programming ............A-22
QuickExam Function ..............A-24
QuickChair Function ............... A-26
Chair Receptacles ..................A-28
Rotational Base
Brake System .......................A-29
Foot Extension ........................A-30
TESTING & ADJUSTMENTS
Primary Fuses ..........................B-2
Foot Control / Touch Pads ........ B-3
Actuators / Limit Switches:
Base .......................................B-7
Back ...................................... B-12
Tilt ......................................... B-17
Gas Springs ............................ B-22
Chair Receptacles ..................B-23
Section B
Main System Transformer ......B-24
Position Sensors .....................B-26
Main PC Board .......................B-32
Foot Extension / Limit Switch .B-35
Rot. Base Brake System ........B-37
(*) Indicates multiple pages due to model / serial number break(s).
WIRING DIAGRAMS
647:
(-001 / -002) Standard Base ...D-2
(-003 / -004) Rotation. Base ...D-3
EXPLODED VIEWS
647:
(-001 / -002) Standard Base ... E-2
(-003 / -004) Rotation. Base ...E-3
Section E
REPAIR PROCEDURES & FORMS
Actuators / Limit Switches:
Base ........................ 003-1739-00
Back ......................... 003-1738-00
Tilt ............................ 003-1915-00
Position Sensors ........ 003-1473-00
Main PC Board .......... 003-1490-00
Upper Glides .............. 003-1509-00
Rotational Base Kit .... 003-1657-00
Gas Springs ............... 003-1741-00
Parts Order Form ....... 004-0755-00
Comments Form ........ 004-0756-00
Color Selector ..... www.midmark.com
ii© Midmark Corporation 2008 SF-1925 [Revised: 2/17/09]
General InformationGeneral Information
Symbols
Ordering Parts
DANGER
Indicates an imminently hazardous situation which
will result in serious or fatal injury if not avoided.
This symbol is used only the most extreme conditions.
WARNING
Indicates a potentially hazardous situation which
could result in serious injury if not avoided.
Caution
Indicates a potentially hazardous situation which may
result in minor or moderate injury if not avoided. It may
also be used to alert against unsafe practices
Equipment Alert
Indicates a potentially hazardous situation which could
result in equipment damage if not avoided.
The symbols below may be used in this manual to represent
the operational status of table functions and components.
Indicates the function / component is working properly.
No action required.
The following information is required when ordering parts:
• Serialnumber&modelnumber
• Partnumberfordesiredpart
(Refer to Section E: Exploded Views & Parts Lists)
Non-warranty parts orders may be faxed to Midmark using
the Fax Order Form in the back of this manual.
For warranty parts orders, call Midmark’s Technical Service
Department with the required information.
Hours: 8:00 am to 5:00 p.m. EST (Monday thru Friday)
Phone: 1-800-Midmark
Serial Number Location
Serial Number
Label
Indicates the function / component is working,
but a problem exists.
Indicates the function is not working at all, or that the
component is faulty.
iii© Midmark Corporation 2008 SF-1925 [Revised: dd/mo/yr]
MA7877i
Specications
Patient Weight (max): 450 lbs (204 kg)
Weight of Chair: Standard Base: 421 lbs (191 kg)
Rotational Base: 506 lbs (230 kg)
Power Cord Length: 8 ft (244 cm)
Fuses (located at power cord inlet): 6.3A, 250V, Type “T”, 5 x 20 mm
Foot Control Voltage: 10 VAC, SELV (Safety Extra Low Voltage)
Chair Receptacle
Maximum Load:
Duty Cycle
(Motor Run Time):
Protection against
ingress of uids:
Classications: Class 1, Type B, Applied Part
Electrical Requirements: See model identication chart below
Regulatory Compliance: See model identication chart below
Equipment not suitable for use in the presence of a ammable anesthetic mixture with air, oxygen, or nitrous oxide.
115 VAC, 3 amps, 50 / 60 Hz
Intermittent Operation
(30 seconds ON - 5 mintes OFF)
Ordinary Equipment
Foot control only: IPX1
Back Function
Full Down: 0° +1/2°
Full Up: 80° +3°
Base Function
Standard Base
Full Down: 19 in. (48 cm)
Full Up: 40 in. (101 cm)
Rotational Base
Full Down: 22.5 in. (57 cm)
Full Up: 43.5 in. (110 cm)
Tilt Function
Full Down: 0° +1/2°
Full Up: 30° +2°
MA7873i
iv© Midmark Corporation 2008 SF-1925 [Revised: 7/21/09]
Model Identication / Compliance Chart
Complies To: Electrical Ratings:
Model Description
647-001 Three-Function Chair
(Base, Back & Tilt)
Non-Programmable
w/Receptacles
647-002 Three-FunctionChair
(Base, Back & Tilt)
Programmable
w/Receptacles
647-003 Three-FunctionChair
(Base, Back & Tilt)
Non-Programmable
w/Rotational Base
647-004 Three-FunctionChair
(Base, Back & Tilt)
Programmable
w/Rotational Base
UL
60601-1
CAN / CSA
22.2,
#601.1-M90
60601-1-2
(EMC)
• • •
• • •
• • •
• • •
EN
VAC
+/- 10%
115 10.5 60
115 10.5 60
115 8.5 60
115 8.5 60
Amps
Cycles
(Hz)
v© Midmark Corporation 2008 SF-1925 [Revised: dd/mo/yr]
Scheduled Maintenance / Cleaning Chart
Interval Inspection / Service Description
Weekly
Semi-Annually
Clean upholstery with appropriate diluted bleach solution 10:1 (water: bleach)
Cleaning
Obvious Damage Visually inspect components for damage that could result in unsafe operation.
Mechanical Operation Check all mechanical functions using the foot control. Repeat using the table mounted touch pads.
Labels / Decals Replace any missing or illegible labels.
Hardware All fasteners must be present and fastened securely.
Electrical System
Wipepaintedmetal&plasticsurfaceswithacleansoftclothandmildcleaner.
Inspect power cord and all wiring for damage.
Be sure all electrical connections are tight.
Date of Service:
Location:
Service Technician:
Model Number:
Serial Number:
Notes:
vi© Midmark Corporation 2008 SF-1925 [Revised: 11/3/2017]
Section ASection A
Troubleshooting
Troubleshooting Chart .......................A-2
Standard Base ...............................A-10
Rotational Base .............................A-12
Base Up / Down...............................A-14
Back Up / Down ...............................A-16
Tilt Up / Down ..................................A-18
Crash Avoidance System ................A-20
Position Programming .....................A-22
QuickExam Function .......................A-24
QuickChair Function ........................A-26
Chair Receptacles ...........................A-28
Rotational Base Brake System ........A-29
Foot Extension.................................A-30
Troubleshooting Chart .......................A-2
Standard Base ...............................A-10
Rotational Base .............................A-12
Base Up / Down...............................A-14
Back Up / Down ...............................A-16
Tilt Up / Down ..................................A-18
Crash Avoidance System ................A-20
Position Programming .....................A-22
QuickExam Function .......................A-24
QuickChair Function ........................A-26
Chair Receptacles ...........................A-28
Rotational Base Brake System ........A-29
Foot Extension.................................A-30
A-1© Midmark Corporation 2008 SF-1925 [Revised: dd/mo/yr]
Troubleshooting Chart
Problem Symptom Probable Cause Check Correction
No functions will operate.
Power light is OFF. Facility supply voltage. Powercordconnections&
facility circuit breaker.
Primary fuse(s) blown. Inspect fuses. Replace faulty fuse(s).
Main system transformer Wire connections between:
power inlet and main PC
board.
Models w/Rotational Base:
Wire connections between:
rotational base PC board and
transformer.
Main PC board If main system transformer is
OK...
Power light is ON. Foot control / touch pad Try activating functions from
each touch pad / foot control.
Secure power cord connections.
Reset circuit breaker if necessary.
Secure loose connections.
If connections are OK, test the
transformer. Refer to: Section B -
Main System Transformer
Secure loose connections.
If connections are OK, perform
EMI Filter Board Test.
Refer to: Section B -
Rotational Base Brake System.
Replace main PC board.
Refer to: Section B -
Foot Control / Touch Pads
Base function not operating
properly.
Models:
Serial Numbers:
647
all
System malfunction Error code LEDs on main PC
board.
No Base Up or Base Down Foot control / touch pad Try activating functions from
each touch pad / foot control.
System malfunction Error code LEDs on main PC
board.
Loose / damaged wire connections Check wire connections to:
base actuator, base limit
switches.Checkblack&white
wire connections between
mainsystemtransformer&
main PC board.
Base actuator / main PC board
Refer to: Section B - Base
Actuator / Limit Switches
(Isolating a Malfunction)
Refer to:
Section B - Main PC Board.
Refer to: Section B -
Foot Control / Touch Pads
Refer to:
Section B - Main PC Board.
Secure any loose connections.
Follow test sequence outlined in
Section B.
[Revised: dd/mo/yr]
A-2© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Problem Symptom Probable Cause Check Correction
Base function not operating
properly. - continued
No Base Up.
Base Down-OK.
Foot control / touch pad Try activating functions from
each touch pad / foot control.
Refer to: Section B -
Foot Control / Touch Pads
-OR-
No Base Down.
Base Up-OK.
Base drifts down. Baseactuator&gassprings With no weight on table, does
Noisy operation (grinding,
squeaking, etc.)
System malfunction Error code LEDs on main PC
board.
(No Base Down)
Crash Avoidance System
(No Base UP):
Base Up limit switch
(No Base Down):
Base Down limit switch
(No Base Down)
Foot extension switch
Base actuator / main PC board
Gas springs / scissor mechanism -
Base actuator
Refer to: Section A -
Crash Avoidance System
Wire connections to limit
switch.
Remove any obstructions
under foot section of table.
Refer to: Section B - Base
Actuator / Limit Switches
(Isolating a Malfunction)
base still drift down?
Refer to: Section B - Base
Actuator / Limit Switches
(Isolating a Malfunction)
Refer to:
Section B - Main PC Board.
Determine appropriate test
procedure(s) based on the
theory of operation for the
Crash Avoidance System.
If connections are OK,
perform Limit Switch Test.
Refer to: Section B -
Base Actuator / Limit Switch
Perform “Crash” Limit Switch Test.
Refer to: Section B - Foot
Extension / “Crash” Limit Switch.
Follow test sequence outlined in
Section B.
IfYES,replacemotorcoupler&
gas springs.
If NO, replace base actuator.
Refer to: Section B - Base
Actuator / Limit Switches
Clean / lubricate gas spring pivot
joints. Wipe guide bars with a
clean, dry cloth.
NEVER lubricate guide bars or
scissor mechanism!
Refer to: Section B - Gas Springs
Follow instructions outlined in
Section B.
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
A-3© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Problem Symptom Probable Cause Check Correction
Base function not operating
properly. - continued
Base function moves slowly,
and/or will not lift patient.
Patient exceeded 450 lb weight
limit
- Inform staff that max patient
weight is 450 lbs.
Back function not operating
properly.
Low voltage to table
Base actuator motor
Gas springs If actuator motor is OK... Replace gas springs.
Basefunctionmovesbriey,then
stops (“beeps”).
No Back Up or Back Down Foot control / touch pad Try activating functions from
Main PC board needs to be
calibrated
System malfunction Error code LEDs on main PC
Base position sensor
Base actuator / main PC board
Check supply voltage.
Required: 115 VAC +10%
Perform Actuator Motor Test.
Refer to: Section B - Base
Actuator / Limit Switches
Calibrate main PC board
board.
Wire connections to sensor.
Perform Output Voltage Test (at
Sensor). Refer to: Section B -
Position Sensors
Perform Actuator Motor Test.
Refer to: Section B - Base
Actuator / Limit Switches
each touch pad / foot control.
Connect adequate supply
voltage.
Follow test sequence outlined in
Section B.
Refer to:
Section B - Gas Springs
Refer to:
Section B - Main PC Board.
Refer to:
Section B - Main PC Board.
Follow test sequence outlined in
Section B.
Follow test sequence outlined in
Section B.
Refer to: Section B -
Foot Control / Touch Pads
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
Loose / damaged wire connections Check wire connections to:
backactuator&backlimit
switches.Check wire connections between main system
transformer&mainPCboard
(black&whitewires).
Back actuator / main PC board
Refer to: Section B -
Back Actuator / Limit Switches
(Isolating a Malfunction)
A-4© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Secure any loose connections.
Follow test sequence outlined in
Section B.
Problem Symptom Probable Cause Check Correctio
Back function not operating
properly. - continued
No Back Up.
Back Down-OK.
Foot control / touch pad Try activating functions from
each touch pad / foot control.
Refer to: Section B -
Foot Control / Touch Pads
-OR-
No Back Down.
Back Up-OK.
Back drifts down. Back actuator / motor coupler
Noisy operation (grinding,
squeaking, etc.)
Back function moves slowly,
and/or will not lift patient.
(No Back Down)
Crash Avoidance System
(No Back UP)
Back Up limit switch
(No Back Down)
Back Down limit switch
Back actuator / main PC board
Back actuator
Patient exceeded 450 lb weight
limit
Low voltage to table
Back actuator motor
Refer to: Section A -
Crash Avoidance System
Wire connections to limit
switch.
Refer to: Section B - Back
Actuator / Limit Switches
(Isolating a Malfunction)
Refer to: Section B - Back
Actuator / Limit Switches
(Isolating a Malfunction)
- Inform staff that max patient
Check supply voltage.
Required: 115 VAC +10%
Perform Actuator Motor Test.
Refer to: Section B - Back
Actuator / Limit Switches
Determine appropriate test
procedure(s) based on the
theory of operation for the
Crash Avoidance System.
Replace back limit switch / bracket
assembly. Refer to:
Section B - Back
Actuator / Limit Switches
Follow test sequence outlined in
Section B.
Replace motor coupler.
Refer to: Section B - Back
Actuator / Limit Switches
Follow instructions outlined in
Section B.
weight is 450 lbs.
Connect adequate supply voltage.
Follow test sequence outlined in
Section B.
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
A-5© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Problem Symptom Probable Cause Check Correction
Back function not operating
properly. - continued
Tilt function not operating
properly.
Backfunctionmovesbriey,then
stops (“beeps”).
No Tilt Up or Tilt Down Foot control / touch pad Try activating functions from
Main PC board needs to be
calibrated
Back position sensor
Back actuator / main PC board
Calibrate main PC board Refer to:
Wire connections to sensor.
Perform Output Voltage Test (at
Sensor). Refer to: Section B -
Position Sensors
Perform Actuator Motor Test.
Refer to: Section B -
Back Actuator / Limit Switches
each touch pad / foot control.
Section B - Main PC Board
Follow test sequence outlined in
Section B.
Follow test sequence outlined in
Section B.
Refer to: Section B -
Foot Control / Touch Pads
No Tilt Up.
Tilt Down-OK.
-OR-
No Tilt Down.
Tilt Up-OK.
Loose / damaged wire connections Check wire connections to:
tilt actuator, tilt down limit
switch.
Tilt actuator / main PC board
Foot control / touch pad Try activating functions from
(No Tilt Up)
Tilt position sensor
(No Tilt Down)
Tilt Down limit switch
Tilt actuator / main PC board
Refer to: Section B -
Tilt Actuator / Limit Switch
(Isolating a Malfunction)
each touch pad / foot control.
Refer to: Section A -
Tilt Up/Down Function
(Tilt Up Operation) for description of proper operation.
Wire connections to limit switch. If connections are OK,
Refer to: Section B - Tilt
Actuator / Limit Switch
(Isolating a Malfunction)
Secure any loose connections.
Follow test sequence outlined in
Section B.
Refer to: Section B -
Foot Control / Touch Pads
Perform Output Voltage Test (at
Sensor). Refer to: Section B -
Position Sensors
perform Limit Switch Test.
Refer to: Section B -
Tilt Actuator / Limit Switch
Follow test sequence outlined in
Section B.
Models:
Serial Numbers:
647
all
[Revised: 1/6/09]
A-6© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Problem Symptom Probable Cause Check Correction
Tilt function not operating
properly. - continued
Seat drifts down. Tilt actuator / motor coupler Replace motor coupler.
Refer to: Section B -
Tilt Actuator / Limit Switch
Noisy operation (grinding,
squeaking, etc.)
Tilt function moves slowly,
and/or will not lift patient.
Tilt actuator
Patient exceeded 450 lb weight
limit
Refer to: Section B - Tilt
Actuator / Limit Switch
(Isolating a Malfunction)
- Inform staff that max patient
Follow instructions outlined in
Section B.
weight is 450 lbs.
Multiple functions are
inoperable. Table “beeps”.
Programming feature does
not work properly.
Tiltfunctionmovesbriey,then
stops (“beeps”).
Inoperable functions may include
any of the following: Base Down,
Back Down, Tilt Up, Tilt Down
Positions cannot be programmed.
- or -
When position button is pressed,
table does not move, or moves to
wrong position.
Low voltage to table
Tilt actuator motor
Main PC board needs to be
calibrated
Tilt position sensor
Tilt actuator / main PC board
Crash Avoidance System Refer to: Section A -
Programming failed. - Reprogram desired position.
Programming process error. Error code LEDs on main PC
Main PC board needs to be
calibrated
Check supply voltage.
Required: 115 VAC +10%
Perform Actuator Motor Test.
Refer to: Section B - Tilt
Actuator / Limit Switch
Calibrate main PC board
Wire connections to sensor.
Perform Output Voltage Test
(at Sensor). Refer to: Section
B - Position Sensors
Perform Actuator Motor Test.
Refer to: Section B -
Tilt Actuator / Limit Switch
Crash Avoidance System
board.
Calibrate main PC board
Connect adequate supply voltage.
Follow test sequence outlined in
Section B.
Refer to:
Section B - Main PC Board
Follow test sequence outlined in
Section B.
Follow test sequence outlined in
Section B.
Determine appropriate test
procedure(s) based on the
theory of operation for the
Crash Avoidance System.
Refer to:
Section A - Position Programming
Refer to:
Section B - Main PC Board
Refer to:
Section B - Main PC Board
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
A-7© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Problem Symptom Probable Cause Check Correction
Rotational base is
malfunctioning.
Rotational brake will not lock. Rotational brake mechanism Unplug table power cord.
If base rotation locks, perform
Rot. Brake Electrical Test.
If base does not lock, inspect
the mechanical brake
components.
Refer to: Section B - Rotational
Base Brake System.
Base wobbles when locked.
- and/or -
Grinding noise when base rotates.
Rotational brake will not unlock. Brake pedal switch Check both brake pedals.
Debrisbetweenupper&lower
castings.
Loose hub screws
Rotation bearings / brake disc
Electro-magnet
- Without separating the castings,
Four screws securing the
upper&lowercastings.
For access instructions, refer
to: Section B - Rotational Base
Brake System (Separating
Upper & Lower Base Castings)
Inspectneedlebearing&
brake disc for damage, debris,
etc.
For access instructions, refer
to: Section B - Rotational base
Brake System (Separating
Upper & Lower Base Castings)
Perform Electro-magnet Test.
Refer to: Section B - Rotational
Base Brake System.
Follow test sequence outlined in
Section B.
remove any debris.
Tighten screws.
Remove debris or replace base if
necessary.
If either pedal works properly,
check connections to faulty
pedal switch. Replace switch if
necessary. Refer to: Section B -
Rotational Base Brake System.
Follow test sequence outlined in
Section B.
Models:
Serial Numbers:
647
all
[Revised: 6/2/16]
A-8© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Problem Symptom Probable Cause Check Correction
No power at chair
receptacles.
Foot extension
malfunctioning.
There is power to the chair, but no
power at the chair receptacles.
Foot extension will not
lock in place.
- or -
Foot extension will not release.
Loose / damaged wire connections
Isolation transformer / receptacles
Foot extension locking
mechanism malfunctioning.
Wire connections between
powerinlet&tablereceptacles
Perform Output Voltage Test.
Refer to: Section B -
Chair Receptacles / Isolation
Transformer
Perform Locking Mechanism
Inspection.
Refer to: Section B -
Foot Extension.
Secure / repair wire connections.
Follow test sequence outlined in
Section B.
Follow instructions outlined in
Section B.
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
A-9© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Power to the Chair (models w/Standard Base)
No functions will operate ...................A-2No functions will operate ...................A-2
This illustration shows only the components that affect ALL CHAIR FUNCTIONS.
Refer to the following page for a detailed description of the power supply to the chair.
8-10 VAC
P9 P10
J1
J15
GN / YL
[Red & orange wires supply 34-37 VAC to power
circuitry for the Tilt actuator, foot control, touch pads,
power light, all limit switches, and position sensors]
GN / YL
J2
J4J3
BK
WH
RD
OR
J8J7J6J5
Main PC
Board
J10J9
J11
J12
J18
J13
J14
MA7838i
[Black & white wires supply 48-54 VAC to
power circuitry for the Base & Back actuators]
Main System
Transformer
BL
BR
N
BL
BR
BR / WH
BL / WH
A
B
C
D
G
H
Power
F1
F2
L
Inlet
8-10 VAC
If power light is OFF, there is no power to PC board.
If power light is ON, proper voltage is present at PC board.
P12
Power
Light
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
A-10© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Power to the Chair (models w/Standard Base)
Facility Supply Voltage
WIth the chair’s power cord properly connected, facility supply voltage
(115 VAC) is supplied thru the cord to the power inlet.
Power Inlet
The voltage setting displayed in the power inlet window
must match facility supply voltage (115 VAC).
Currentowsthrutwofusesinthepowerinlet,tothemainsystemtransformer.
Main System Transformer
Note
This transformer is protected from overload by a thermal cutout
feature. This will automatically reset when the transformer cools.
Line voltage (115 VAC) is supplied to the main system transformer. The trans-
formerreducesthevoltageandcurrentowstothemainPCboardthrutwo
separate windings (four wires).
[The black & white wires supply 48-54 VAC to power circuitry for the Base &
Back actuators only]
[The red & orange wires supply 34-37 VAC to power circuitry for the Tilt actuator,
foot control, touch pads, power light, all limit switches, and position sensors].
Equipment Alert
Voltage setting displayed in the power inlet window
must match facility supply voltage (115 VAC).
115V
115V
MA7840i
Power Indicator Light
When voltage is applied to the PC board, the power light is illuminated.
Main PC Board
Circuitry on the PC board provides the required voltage to power all
of the table’s components: foot control, actuators, limit switches, and
position sensors.
Foot Control / Touch Pads
Circuitry on the main PC board supplies 8-10 VAC to the foot control
&touchpads.
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
A-11© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Power to the Chair (models w/Rotational Base)
No functions will operate ...................A-2No functions will operate ...................A-2
This illustration shows only the components that affect ALL CHAIR FUNCTIONS.
Refer to the following page for a detailed description of the power supply to the chair.
[Black & white wires supply 48-54 VAC to
power circuitry for the Base & Back actuators]
[Red & orange wires supply 34-37 VAC to power
circuitry for the Tilt actuator, foot control, touch pads,
power light, all limit switches, and position sensors]
J1
J15
GN / YL
WH
BK
J10J9
8-10 VAC
J11
J12
P12
J13
J14
If power light is OFF, there is no power to PC board.
If power light is ON, proper voltage is present at PC board.
8-10 VAC
J2
J4J3
J8J7J6J5
Main PC
Board
J18
Power
Light
OR
RD
Rotational
Base
PC Board
J10
J9
OR
RD
WH
BK
Main System
Transformer
J3
J7
BL
BR
BR/WH
J5
BL/WH
J12
J2
GN / YL
J4
J6
C
A
B
GN / YL
BL
GN / YL
BL
BR
D
G
H
BR
L
N
J4
EMI Filter
J6
PC Board
J5
J2
J3
MA7839i
J1
Power Inlet
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
A-12© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Power to the Chair (models w/Rotational Base)
Facility Supply Voltage
WIth the chair’s power cord properly connected, facility supply
voltage (115 VAC) is supplied thru the cord to the power inlet.
Power Inlet / EMI Filter Board
The voltage setting displayed in the power inlet window
must match facility supply voltage (115 VAC).
CurrentowsfromthepowerinletthrutheEMIlterboard,then
back thru the power inlet fuses to the rotational base PC board.
Rotational Base PC Board
CurrentowsthrutherotationalbasePCboardtothemainsystem
transformer.Thetransformerreducesthevoltageandcurrentows
back to the rotational base PC board.
Circuitry on the rotational base PC board provides the required
voltage to power the rotational base brake system.
The reduced voltage is supplied to the main PC board thru the
rotational bse PC board.
Main System Transformer
Note
This transformer is protected from overload by a thermal cutout
feature. This will automatically reset when the transformer cools.
Line voltage (115 VAC) is supplied to the main system transformer
thru the rotational base PC board. The transformer reduces the volt-
ageandcurrentowsbacktotherotationalbasePCboard,thento
the main PC board thru two separate windings (four wires).
Equipment Alert
Voltage setting displayed in the power inlet window
must match facility supply voltage (115 VAC).
115V
115V
MA7840i
Main System Transformer - continued
[The black & white wires supply 48-54 VAC to power circuitry for the Base & Back
actuators only]
[The red & orange wires supply 34-37 VAC to power circuitry for the Tilt actuator,
foot control, touch pads, power light, all limit switches, and position sensors].
Power Indicator Light
When voltage is applied to the PC board, the power light is illuminated.
Main PC Board
Circuitry on the PC board provides the required voltage to power all of the table’s
components: foot control, actuators, limit switches, and position sensors.
Foot Control / Touch Pads
CircuitryonthemainPCboardsupplies8-10VACtothefootcontrol&touchpads.
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
A-13© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Base UP / DOWN Function
No Base Up or Base Down................A-2
No Base Up. Base Down - OK ..........A-3
No Base Down. Base Up - OK ..........A-3
Base drifts down ................................A-3
Noisy operation
(grinding, squeaking, etc) ................A-3
Function moves slowly, and/or
will not lift patient .............................A-4
Function moves briey,
then stops and “beeps” ....................A-4
No Base Up or Base Down................A-2
No Base Up. Base Down - OK ..........A-3
No Base Down. Base Up - OK ..........A-3
Base drifts down ................................A-3
Noisy operation
(grinding, squeaking, etc) ................A-3
Function moves slowly, and/or
will not lift patient .............................A-4
Function moves briey,
then stops and “beeps” ....................A-4
This illustration shows only the components that affect the Base UP / DOWN function.
Refer to the following page for a detailed description of Base UP / DOWN operation.
Base
Actuator
WH
BK
WH
BK
Choke
WH
BK
J2
J1
J15
BK
WH
Models:
Serial Numbers:
J4J3
[Black & white wires supply 48-54 VAC to
power circuitry for the Base & Back actuators]
Main System
Transformer
647
all
[Revised: dd/mo/yr]
J8J7J6J5
Main PC
Board
J18
J10J9
J11
J12
J13
J14
MA7841i
P12
P13
Note: On models w/rotational base, the main system
transformer connections are supplied thru the
Rotational Base PC board (not shown).
[Only the wires that affect this function are shown]
If power light is OFF:
Refer to ‘Power to the Table’ for troubleshooting.
Power
Light
YL
OR
If power light is ON:
Proper voltage is present at PC board.
RD
1
2
3
COM
NC
NO
COM
NC
NO
Base
Sensor
Base Up
Limit Switch
Base Down
Limit Switch
BN
BK
GN
GN
A-14© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Base UP / DOWN Function
Is there power to the table?
When voltage is present at the PC board, the
power light is illuminated.
[Refer to ‘Power to the Table’ (page A-2) for
description of current ow to the PC board].
Power to Foot Control / Touch Pads
Circuitry on the PC board supplies 8-10 VAC
tothefootcontrol&touchpads.
Base Up Operation
When the Base Up function is activated, current
owsthruthefootcontrol/touchpadstothe
main PC board. Circuitry on the main PC board
supplies approximately 48 VDC to the base
actuator motor.
The actuator motor runs and raises the table.
Note
The main PC board continuously monitors the base
up limit switch and the base position sensor.
If the base up limit switch is tripped (open), the
Base Up function will not operate.
If the base position sensor detects that that table
has reached its upper limit, the Base Up function
will not operate.
Actuator motor runs until:
1. Foot control / touch pad button is released.
2. Base Up limit switch is tripped.
3. Emergency Stop button is pressed.
4. Position sensor detects upper limit.
5. Overcurrent protection tripped
6. Software timeout is reached (25 seconds).
Base Down Operation
When the Base Down function is activated,
currentowsthruthefootcontrol/touchpads
to the main PC board. Circuitry on the main PC
board supplies approximately 48 VDC to the
base actuator motor.
The actuator motor runs and lowers the table.
Note
The main PC board continuously monitors the base
down limit switch and the base position sensor.
If the base down limit switch is tripped (open), the
Base Down function will not operate.
If the base position sensor detects that the table is
in a potential “crash position”, or that the base has
reached its lower limit, the Base Down function will
not operate*.
Actuator motor runs until:
1. Foot control / touch pad button is released.
2. Base Down limit switch is tripped.
3. Crash Avoidance System activated*.
4. Emergency Stop button is pressed.
5. Position sensor detects lower limit.
6. Overcurrent protection tripped
7. Software timeout is reached (25 seconds).
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
* Refer to Section A: Crash Avoidance System
for a detailed description of “crash position”,
and the functions that are disabled.
A-15© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Back UP / DOWN Function
No Back Up or Back Down ................A-4
No Back Up. Back Down - OK ...........A-5
No Back Down. Back Up - OK ...........A-5
Back drifts down ................................A-5
Noisy operation
(grinding, squeaking, etc) ................A-5
Function moves slowly, and/or
will not lift patient .............................A-5
Function moves briey,
then stops and “beeps” ....................A-6
No Back Up or Back Down ................A-4
No Back Up. Back Down - OK ...........A-5
No Back Down. Back Up - OK ...........A-5
Back drifts down ................................A-5
Noisy operation
(grinding, squeaking, etc) ................A-5
Function moves slowly, and/or
will not lift patient .............................A-5
Function moves briey,
then stops and “beeps” ....................A-6
This illustration shows only the components that affect the Back UP / DOWN function.
Refer to the following page for a detailed description of Back UP / DOWN operation.
Back
Actuator
Choke
BL
J2
J1
J15
BK
WH
BR
J4J3
Main System
Transformer
Note: On models w/rotational base, the main system
transformer connections are supplied thru the
Rotational Base PC board (not shown).
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
J8J7J6J5
Main PC
Board
J18
J10J9
J11
J12
J13
J14
MA7842i
[Black & white wires supply
48-54 VAC to power circuitry
for the Base & Back actuators]
If power light is OFF:
Refer to ‘Power to the Table’
for troubleshooting.
If power light is ON:
Proper voltage is present at PC board.
P12
P11
Power
Light
[Only the wires that affect this function are shown]
BL
3 3
BK
4
4
3
3
BR
WH
GY
VI
YL
RD
2
2
1
1
WH
GY
4
4
3
3
VI
2
2
YL
1
1
RD
NC
NO
COM
NC
NO
COM
Back
Position
Sensor
Back Up
Limit Switch
Back Down
Limit Switch
BK
WH
WH
VI
1
GY
2
YL
3
A-16© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Back UP / DOWN Function
Is there power to the table?
When voltage is present at the PC board,
the power light is illuminated.
[Refer to ‘Power to the Table’ (page A-2) for
description of current ow to the PC board].
Power to Foot Control / Touch Pads
Circuitry on the PC board supplies 8-10 VAC
tothefootcontrol&touchpads.
Back Up Operation
When the Back Up function is activated, current
owsthruthefootcontrol/touchpadstothe
main PC board. Circuitry on the main PC board
supplies approximately 48 VDC to the back
actuator motor.
The actuator motor runs and raises the back
section.
Note
The main PC board continuously monitors the back
up limit switch and the back position sensor.
If the back up limit switch is tripped (closed), the
Back Up function will not operate.
If the back position sensor detects that the back
has reached its upper limit, the Back Up function
will not operate.
Actuator motor runs until:
1. Foot control / touch pad button is released.
2. Back Up limit switch is tripped.
3. Emergency Stop button is pressed.
4. Position sensor detects upper limit.
5. Overcurrent protection tripped
6. Software timeout is reached (30 seconds).
Back Down Operation
When the Back Down function is activated,
currentowsthruthefootcontrol/touchpads
to the main PC board. Circuitry on the main PC
board supplies approximately
44 VDC to the back actuator motor.
The actuator motor runs and lowers the back
section.
Note
The main PC board continuously monitors the back
down limit switch and the back position sensor.
If the back down limit switch is tripped (open), the
Back Down function will not operate.
If the back position sensor detects that the table
is in a potential “crash position”, or that the back
section has reached its lower limit, the Back Down
function will not operate*.
Actuator motor runs until:
1. Foot control / touch pad button is released.
2. Back Down limit switch is tripped.
3. Crash Avoidance System activated*.
4. Emergency Stop button is pressed.
5. Position sensor detects lower limit.
6. Overcurrent protection tripped
7. Software timeout is reached (30 seconds).
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
* Refer to Section A: Crash Avoidance System
for a detailed description of “crash position”,
and the functions that are disabled.
A-17© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Tilt UP / DOWN Function
No Tilt Up or Tilt Down ......................A-6
No Tilt Up. Tilt Down - OK .................A-6
No Tilt Down. Tilt Up - OK .................A-6
Seat drifts down .................................A-7
Noisy operation
(grinding, squeaking, etc) ................A-7
Function moves slowly, and/or
will not lift patient .............................A-7
Function moves briey,
then stops and “beeps” ....................A-7
No Tilt Up or Tilt Down ......................A-6
No Tilt Up. Tilt Down - OK .................A-6
No Tilt Down. Tilt Up - OK .................A-6
Seat drifts down .................................A-7
Noisy operation
(grinding, squeaking, etc) ................A-7
Function moves slowly, and/or
will not lift patient .............................A-7
Function moves briey,
then stops and “beeps” ....................A-7
This illustration shows only the components that affect the Tilt UP / DOWN function.
Refer to the following page for a detailed description of Tilt UP / DOWN operation.
Tilt
Actuator
BR
J2
J1
J4J3
Main PC
Board
J15
If power light is OFF:
Models:
Serial Numbers:
Refer to ‘Power to the Table’ for troubleshooting.
If power light is ON:
Proper voltage is present at PC board.
647
all
[Revised: dd/mo/yr]
[Only the wires that affect this function are shown]
5 5
BK
RD
BL
J8J7J6J5
J18
J10J9
J11
J12
J13
J14
P11
WH
P12
WH
WH
YL / WH
VI
YL
Power
Light
BK
4
4
3
3
RD
2
2
1
1
WH
4
4
3
[not used]
2
1
3
4
[Connected to Back Limit Switch Harness]
3
2
1
4
4
BR
3
3
2
2
1
1
1 1
VI
YL
WH
COM
NC
RD
NO
VI
3
BR
2
YL
1
Tilt Down
Limit Switch
Tilt
Position
Sensor
A-18© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Tilt UP / DOWN Function
Is there power to the table?
When voltage is present at the PC board,
the power light is illuminated.
[Refer to ‘Power to the Table’ (page A-2) for
description of current ow to the PC board].
Power to Foot Control / Touch Pads
Circuitry on the PC board supplies 8-10 VAC
tothefootcontrol&touchpads.
Tilt Up Operation
When the Tilt Up function is activated, current
owsthruthefootcontrol/touchpadtothemain
PC board. Circuitry on the main PC board supplies approximately 48 VDC to the tilt actuator
motor.
The actuator motor runs and raises the seat
section.
Note
The main PC board continuously monitors the tilt
position sensor.
When the tilt position sensor detects that the seat
section has reached its upper limit, or that the table
is in a potential “crash position”, the Tilt Up function
will not operate*.
Actuator motor runs until:
1. Foot control / touch pad button is released.
2. Crash Avoidance System activated*.
3. Emergency Stop button is pressed.
4. Position sensor detects upper limit.
5. Overcurrent protection tripped
6. Software timeout is reached (30 seconds).
Tilt Down Operation
When the Tilt Down function is activated,
currentowsthruthefootcontrol/touchpad
to the main PC board. Circuitry on the main PC
board supplies approximately
48 VDC to the tilt actuator motor.
The actuator motor runs and lowers the seat
sectionbacktoaatposition.
Note
The main PC board continuously monitors the tilt
down limit switch and the tilt position sensor.
If the tilt down limit switch is tripped (open), the tilt
Down function will not operate.
If the tilt position sensor detects that the table is in
a potential “crash position”, or that the seat section
has reached its lower limit, the Tilt Down function
will not operate*.
Actuator motor runs until:
1. Foot control / touch pad button is released.
2. Tilt Down limit switch is tripped.
3. Crash Avoidance System activated*.
4. Emergency Stop button is pressed.
5. Position sensor detects lower limit.
6. Overcurrent protection tripped
7. Software timeout is reached (30 seconds).
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
* Refer to Section A: Crash Avoidance System
for a detailed description of “crash position”,
and the functions that are disabled.
A-19© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Crash Avoidance System
Multiple functions are inoperable
(chair “beeps”) .................................A-7
Multiple functions are inoperable
(chair “beeps”) .................................A-7
The Crash Avoidance System prevents damage to the table by disabling certain functions if a
potential crash position is detected.
This illustration shows only the components that are monitored by the Crash Avoidance System.
Refer to the following page for a detailed description of “crash position” and how the system functions.
[Only the wires that affect this function are shown]
If actuator(s) are not working properly, refer to that
section for troublshooting (ex. Base Up / Down).
[Connected to Tilt Down Limit Switch Harness]
[not used]
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
If power light is OFF:
Refer to ‘Power to the Table’ for troubleshooting.
If power light is ON:
Proper voltage is present at PC board.
[Connected to Back Limit Switch Harness]
A-20© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Crash Avoidance System
When are functions disabled?
The main PC board continuously monitors
the three position sensors, as well as the foot
extension switch.
Based on the position sensor readings, circuitry
on the main PC board estimates the position
of the back section. If the estimated position
indicatesapotentialcollisionwiththeoor,the
Base Down, Tilt Up, and/or Back Down
functions are disabled.
If the foot extension switch is tripped* (open),
the Base Down and Tilt Down functions will be
disabled.
[* The foot extension switch is tripped when
upward pressure is applied to the foot section].
When are functions restored?
Functionality is restored when one or more of
the axis are moved out of the potential crash
position, and / or when the foot extension switch
is no longer tripped (closed).
What is “Crash Position”?
The table is considered to be in a potential crash
position when:
A. The Base, Back, and Tilt position sensors
indicate that the back section is
approximatelyxin(xxcm)fromtheoor.
B. The foot extension switch is tripped (open).
[This is designed to prevent damage due to
objects being trapped under the foot section].
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
A-21© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Position Programming
Positions cannot be programmed ......A-7
Chair does not move .......................A-7
Chair moves to wrong position ........A-7
Positions cannot be programmed ......A-7
Chair does not move .......................A-7
Chair moves to wrong position ........A-7
The programming feature allows the user to store up to three frequently used table positions.
This illustration shows only the components that affect the position programming.
Refer to the following page for a detailed description of this feature.
If actuator(s) are not working properly, refer to that
section for troublshooting (ex. Base Up / Down).
[Only the wires that affect this function are shown]
J2
J1
J15
Models:
647
Serial Numbers:
J4J3
all
[Revised: dd/mo/yr]
J8J7J6J5
Main PC
Board
J18
J10J9
J11
J12
J13
J14
MA7845i
Power
Light
GY
YL / WH
VI
YL
If power light is OFF:
Refer to ‘Power to the Table’ for troubleshooting.
If power light is ON:
Proper voltage is present at PC board.
4
3
2
1
1 1
GY
4
BR
3
2
1
VI
YL
RD
1
BN
2
BK
3
VI
BR
YL
VI
GY
YL
Base
Position
Sensor
3
2
1
1
2
3
Tilt
Position
Sensor
Back
Position
Sensor
A-22© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Position Programming
When are functions disabled?
The three position sensors continuously monitor
thepositionofeachaxis(Base,Back,&Tilt).
This information is transmitted to the PC board.
When a table position is properly programmed
into the PC board’s memory, the position of
each axis is recorded based on the readings
from the position sensors.
Recalling a programmed position
When a programmed position is recalled, the
PC board activates the required functions (all
at the same time) until the readings from the
position sensors match those of the recorded
position.
To program a table position...
A) Move the table to desired position.
B) Press the Program button (one “beep”).
C) Press the desired Position button (1, 2, or 3).
(three “beeps”)
Tip: You must press the desired Position button within
five seconds of pressing the Program button.
To recall a table position...
Press the desired Position button (1, 2, or 3) momentarily.
Note: In the event of a malfunction, press the Stop button to terminate movement.
Stop
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
Program
Position Buttons
Position
Button
Program
Stop
A-23© Midmark Corporation 2008 SF-1925 Always verify model & serial number
Position
Buttons
QuickExam Function
ThisfunctionactivatestheBaseUp&TiltUpfunctionssimultaneouslytomovethetableinto“examposition”.
This illustration shows only the components that affect the QuickExam function.
Refer to the following page for a detailed description of this feature.
[Only the wires that affect this function are shown]
If actuator(s) are not working properly, refer to that
section for troublshooting (ex. Base Up / Down).
Models:
Serial Numbers:
647
all
[Revised: dd/mo/yr]
If power light is OFF:
Refer to ‘Power to the Table’ for troubleshooting.
If power light is ON:
Proper voltage is present at PC board.
A-24© Midmark Corporation 2008 SF-1925 Always verify model & serial number
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