Brookfield Industries NB-500 User manual

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For All Door Operator Model Numbers
for Swinging and Sliding Doors
SWINGING AND SLIDING DOOR OPERATORS FOR LEAD
SHIELDED DOORS

Brookfield Industries, Inc.
NB-4120-2-DC Single/Bi-Parting
COMMERICAL/INDUSTRIAL
SLIDING
DOOR OPERATOR
MANUAL
(6th Edition 01/01/2021)*
*Incorporates Maintained Contact to Close per UL 325 Entrapment
and improved safety relay.
US Patent No. 6,177,771 B1

Table of Contents
• Important Instructions for Installation
• Important Safety Instructions
• Overview
• Installation Instructions
• Installation Instructions for Emergency Hand wheel
• HMI Instructions
• Door Position Setup Instructions
• NB-4120-2-DC Drawings: NB-4120-2C4, NB-4120-2DC4,NB-4120-2DC8,
NB-4120-2DC9, NB-4120-2P2, NB-4120-2-DC-Travel, NB-4120-2-DC-
SingleSlide-1
• Terminal Strip Hookup Legend (Power Supply and Class 2 Voltages)
• Wiring Diagrams
• Parameters
• Maintenance Intervals
• Safety Systems
• Limited Warranty
• Sliding Door Operator Troubleshooting

WARNING!
IMPORTANT INSTALLATION INSTRUCTIONS
IMPROPER INSTALLATION CAN LEAD TO SEVERE INJURY OR DEATH
READ AND FOLLOW ALL INSTRUCTIONS
• Commercial/Industrial Sliding Door Operator that has exposed moving parts capable of causing injury to persons
or employs a motor deemed indirectly accessible by UL 325,10.6 by virtue of its location above the floor shall include:
(a) Install the operator at least 8 ft (2.44 m) or more above the floor; or
(b) If the operator must be installed less than 8 ft (2.44 m) above the floor, exposed moving parts must be
protected by covers or guarding, provided by the operator or door manufacturer; or
(c) Both (a) and (b)
• Install only on a properly operating and balanced door within the rated values for door weight, door width and
operating forces as stated on the ratings label
• Do not connect door operator to source of power until instructed to do so
• This door operator shall be installed and serviced by a qualified technician, electrician or electrical maintenance
person familiar with its operation and the potential hazards involved.
• Any person performing installation or service on this product shall read this manual first. Proper installation includes
following all steps outlined in the Installation Instructions and the settings specified under the Parameters section.
• Assure all electrical wiring and grounding is installed as specified in this manual and as required by any local codes.
Proper installation can also reduce the risk of electrical shock, fire or explosion.
• Locate activation switches or push button stations: (a) within sight of the door, (b) at a minimum height of 5 ft (1.53 m)
above floors, landings, steps, or any other adjacent walking surface (c) away from moving parts of the door.
• As described in this manual, the Stop command controlled by the motor drive is not intended to be a fail safe or
Emergency Stop (E-Stop) since it does not prevent the motor drive from malfunctioning. This can only be
accomplished by disconnecting the AC power to the operator (terminals L1 and N).
• This door operator is to be a permanent or “hard” wired connection to the supply voltage. The electrical contractor
shall install a dedicated breaker or line switch to disconnect each ungrounded pole of the door operator from the
supply voltage. Each ungrounded pole shall have a minimum of 3mm contact separation.
• If this model is equipped with a manual release, disengage pin(s) between door and door operator before manually
moving the door.

WARNING!
IMPORTANT SAFETY INSTRUCTIONS
IMPROPER USAGE CAN LEAD TO SEVERE INJURY OR DEATH
READ AND FOLLOW ALL INSTRUCTIONS
• Commercial/Industrial Sliding Door Operator for trained traffic* use only. The manufacturer of this product does not
include external safety devices as a standard feature.
• External safety devices are required on this door operator. The installer is solely responsible for selecting and installing
the correct safety devices to prevent severe injury or death. Refer to the Terminal Strip Hookup in this manual for proper
wiring and to the owner’s manual of the external safety device manufacturer for proper installation and use.
• No person shall perform any service or activate this door operator unless they have been properly trained in its safe
usage and have read the owner’s manual.
• Never let children operate or play with door controls.
• Before activating this door operator, check the following:
1. Assure that all personnel are clear of the path of this operator and the door that it is attached to.
2. Assure that all fingers, hands, feet, limbs and articles of clothing are clear of all moving parts and pinch points.
• Personnel should keep away from a door in motion and keep the moving door in sight until it is completely closed or open.
NO ONE SHOULD CROSS THE PATH OF A MOVING DOOR.
• Test the door’s safety features at least once a month. Make any adjustments or repairs as necessary and retest. Failure
to do so may cause severe injury or death.
• KEEP DOORS PROPERLY OPERATING AND BALANCED. Refer to door manufacturer’s manual. Have repairs done
by trained technicians.
• Prior to performing any service on this product (including the replacement of any fuses or circuit breakers), disconnect the
operator from the supply voltage.
• For continued protection against fire, replacement fuses or circuit breakers shall be of the same type and ratings as those
being replaced.
*Defined in ANSI 156.10 as a controlled group of people trained in the safe use and operation of a particular door installation.
SAVE THESE INSTRUCTIONS

Overview
The NB-4120-2-DC, Single and Bi-Parting Sliding Door Operator, is designed and tested for
lead shielding doors weighing up to 35,000 lbs (single door)/17,500 lbs (each bi-parting door),
operating at linear speeds of 6.0 in/sec maximum (single door)/12.0 in/sec maximum (bi-parting
doors), or a maximum horizontal operating force of 700 lbs (single door) or 350 lbs (each bi-
parting door). The drive train features a 2” wide (H) pitch, polyurethane, steel reinforced timing
belt, coupled to a ¾ hp, 90VDC, helical-bevel (high torque) gear motor. Since the drivetrain
features a ¾ hp DC motor, this operator also includes a Battery Backup System and Manual
Operation as a redundant backup for power interruption. Applications involving heavier doors at slower
speeds/acceleration rates should be referred to the Engineering Department.
The NB-4120-2-DC is designed to be used in conjunction with an existing linear bearing/rail
system capable of supporting heavy doors with a low coefficient of friction or standard beam
trolley supports for hanging the door. The open ended style timing belt normally clamps to
the side of the door carriage/attachment structure. Once the timing belt has been properly
aligned and pre-loaded, in addition to the motor control parameters being correctly set, the
NB-4120-2-DC will provide many years of maintenance free service.
This power open/power close electro-mechanical operator with its state of the art
components, make it the strongest, most reliable and easiest to install in the industry today.
Refer to the Wiring Legend for Terminal Strip Hookup for all open, close, stop and
External Safety Device inputs, which are all Class (2) 24VDC normally open momentary
contact (except the stop input, terminal #10, which is a normally closed input). Power
supply hookups for both Class (2) 24VDC, and 230VAC, 3 phase are also indicated. The
PLC then processes all this information, in addition to many other features for proper control
of these heavy lead or concrete doors. This door operator is patented under US Patent No.
6,177,771 B1.
The NB4120-DC Commercial/Industrial Sliding Door is compliant with UL 325 under
Section External Entrapment Protection featuring Fail Safe Monitoring, providing all
External Safety Devises are wired and installed per this manual.
We are Authorized to Mark the NB-4120-DC with the ETL and CE markings from Intertek
Testing Services to assure compliance with UL 325, FCC Part 15 (Emissions) and the
following International Standards: EN 60335-1 and -2 (Safety), EN 61000-6-2 (Immunity)
and EN 61000-6-4 (Emissions). The “listing” reports specifically refer to the heavy
commercial/industrial doors associated with linear accelerator rooms.
Logic Control:
This Operator offers the latest technology in PLC (Programmable Logic Control). The
following (3) modules snap to a DIN rail base: CPU (Central Processing Unit) - processes
and stores data in its internal register such as door position presets, inputs from pushbutton

stations and outputs to motor controls. This extremely compact unit houses (8) LED 24
VDC inputs and (6) LED outputs with (3) isolated commons.
Analog/Digital Converter- converts the analog signal of the Rotary Position Transducer to
a digital value.
Class (2) 24 VDC Power Supply- converts 110 supply voltage to Class (2) 24VDC power
to operate the CPU, A/D converter, Rotary Position Transducer and presence sensors.
These plug-in modules with LED make diagnostics and replacement of parts easy and quick
to perform.
Interface with the PLC is necessary to adjust Door Position Presets in the field. This is
accomplished by plugging in an 8- Pin Phoenix connector to the back of the Human
Machine Interface (HMI) and a round female connector into the side panel of the operator.
The HMI is a hand held, touch screen device that is purchased separately.
The CPU has been programmed to adjust on the fly, such door position presets as Back
Check, Full Open, Latch Check and Full Closed.
Input commands to be processed by the PLC, are done so by making the appropriate
connections on the Terminal Strip Hookup. By connecting a separate normally open
SPST switch between terminals 1 and 14 to open, terminals 1 and 13 to partially open,
terminals 1 and 12 to close, and a normally closed SPDT switch to terminals 1 and 10 to
stop the door, provides the customer discrete control of each input from a momentary
contact push button station (not included). These commands can also be activated by
presence sensors, or control mats. Reversing the direction of the door while it’s moving
(dynamic) can be accomplished by simply pressing the appropriate switch to change
direction. We do not include any activation devices or push button stations with our door
operators.
The NB-4120 features momentary contact Input commands for External Safety Devices
that comply with UL 325 Section External Entrapment Protection featuring Fail Safe
Monitoring. These devices are normally door mounted, 4-wire reversing edge contact
type sensors that reverse the door while closing. However, they can be substituted with
non-contact type presence sensors providing the external wiring is compatible with our
internal wiring. Note: The door will not be allowed to close unless these sensors are
correctly wired per this manual. When installing contact type sensors, assure they are
properly secured to the leading edge of the door with sufficient spacing and length to assure safe
activation (refer to the owner’s manual). Momentary contact Input commands and a low
voltage Class (2) power supply are also provided for additional (redundant) sensors,
such as non-contact type presence sensors that are frame mounted. brookfield
industries does not manufacture nor do we include External Safety Devices with any of our
door operators. The installer is solely responsible for selecting the correct sensors to
prevent injury. To assure that external safety devices are properly installed and adjusted
correctly, refer to the owner’s manual for that devise. For proper wring, refer to Terminal
Strip Hookup and the Wiring Diagram included in this manual.

The NB-4120 also features a maintained contact (constant pressure/dead man)
Input (Terminals 1 & 20) to close the door that complies with UL 325, Entrapment. For
proper wiring to this input, please refer the Terminal Strip Hookup.
The user now has the flexibility of choosing either one of the above methods: Entrapment by
means of maintained contact or External Entrapment Protection through safety sensors.
Both methods can be employed by simply connecting to both inputs. The maintained
contact could then be utilized as an emergency override for closing the door in case the
tape switches fail. This allows the door to stay in operation until the contact sensors can be
repaired.
The Stop command (normally closed terminal #10) will stop the door in any position when
activated but it will not prevent a motor drive from malfunctioning nor is it a true emergency
stop. Emergency Stop (E-Stop) can only be accomplished by disconnecting AC
power to the operator (Terminal L1, L2, L3 and Terminal N).
The NB-4120 features the same Absolute Position Feedback Control system and
software as other brookfield industries, inc. door operators. There are no limit or
proximity switches to adjust or install for any of the door positions under normal operation.
Simply adjust the door’s positioning presets as required by interfacing with the PLC via a
hand held Human Machine Interface (purchased separately).
A Rotary Position Transducer attached to the gear motor output shaft provides the
position of the door. As the door changes position, the output signal from the transducer
varies in value. This signal, once converted to a digital value, is stored in the CPU for
further processing. This devise does not need to be “homed” or reset if there is a power
loss or electrical noise nor does it need to go through “learn speed” after power up or after
adjustments have been made.
Motor Control:
The NB-4120-2-DC utilizes a state of the art Regenerative (4-Quadrant) 90 VDC Motor
Control. This provides the best assurance that the door’s high inertia characteristics will
not “overhaul” (or “freewheel”) the motor; thus, resulting in controlled door motion. The NB-
4120 now features a multi-speed board that attaches to the top of the motor control. The
logic panel is greatly simplified with the elimination of the external speed pots and the
associated wiring. The new multi-speed board features control of (4) independent speeds.
The NB-4120 now has the flexibility of controlling separate creep close speeds (Preset 1)
and creep open speeds (Preset 2) as well as close speeds (Preset 3) and open speeds
(Preset 4). The motor control also features additional trimpots, which greatly improve the
performance of the drive and motion profile of such heavy doors. The DB (Dead Band)
trimpot sets the amount of main speed trimpot rotation to initial output voltage and controls
the amount of delay before regeneration starts. If not properly set, the motor may oscillate

or continue to hum. The RESP (Response) trimpot adjusts the dynamic response of the
system; therefore, increasing this setting will increase response time (if set too high,
unstable operation may result). The IR Comp trimpot determines the amount in which the
motor speed is held constant as the motor load changes. For example, if set too low, the
motor may not obtain the desired speed fast enough or not at all. If set too high, the motor
may oscillate. The RCL (Reverse Current Limit) trimpot and FCL (Forward Current Limit)
trimpot adjusts the armature current limit or motor torque in their respective directions.
When properly set, the operator will have sufficient torque to operate in both directions,
while at the same time limiting the current to the motor. This will prevent damage to any of
the mechanical components of the door operator (also eliminates the need for unreliable
and hard to adjust manual slip or electromagnetic clutches).
The MAX (maximum speed) trimpot adjusts the voltage or speed of the motor in the forward
and reverse directions. The FACC (Forward Acceleration) trimpot adjusts the acceleration
time in the forward direction as a function of the maximum rated motor speed. It also
controls the Reverse Deceleration time. The RACC (Reverse Acceleration) trimpot adjusts
the acceleration time in the reverse direction as a function of the maximum rated motor
speed. It also controls the Forward Deceleration time.
Overload Protection for the DC motor is provided by using the appropriate line fuse to the
110VAC power supply of the motor control (see wiring diagram) and by the proper setting of
the Reverse Torque and Forward Torque trimpots, which controls the amount of DC
current to the motor in both directions.
Drive Train:
The NB-4120-2-DC is a linear drive system comprised of a 2” wide XH polyurethane steel
reinforced timing belt driven by a single phase, 3/4 hp, 1750 RPM, DC motor that is coupled to a
helical-bevel (92:1) gear reducer with an output torque rating of 3540 lb-in and overhang load
rating of 1250 lbs. The timing belt is open-ended and is attached to the doors with matching
aluminum clamping plates. The belt is adjusted for pre-tension and tracking from the take-up end
frames. A properly installed and adjusted timing belt will provide operating forces up to 700 lbs
(total both doors) at the maximum speed of 6 in/sec (each leaf in opposite directions).
Supply Voltage:
115 VAC, (+/- )10%, 50/60 Hertz, single phase. Motor control and power supply are
equipped with in-line circuit breakers. Surge protection and filtering of the supply voltage is
featured to protect door operator components and to assure reliable performance (immunity)
as well as minimizing RF noise (emissions).
For European installations we offer a 230 VAC single phase to 115 VAC 50 Hz conversion.
Please specify when ordering.
Current Consumption (AC Line Input):
Maximum current: 12 amps

Manual Operation:
In case of loss of power, manual operation shall be less than 50 lbs to open per UL 325
Interruption of Power. This is accomplished by engaging a flexible shaft into the rear shaft
of the motor via a remote control cable. A lever arm, which activates the remote control
cable, and a 7” diameter hand wheel, which is connected to the flexible shaft, are contained
in a NEMA 1 box. Approximate opening time, while manually operating the hand wheel, is
about 2.5 minutes.
Battery Backup (standard):
When power is interrupted, and if the door is in any position other than fully open, the
battery backup will be activated and provide low voltage DC power directly to the motor.
The system is designed to open the door once for each power interruption at a constant
speed. This system is not designed to open and close the door repeatedly. A float
charger is included to provide a constant charge on the battery. These components are
installed in the NEMA 1 control panel. Also included is an end of travel limit switch, which
must be installed so that it disconnects power to the motor when the door is fully open. (this
limit switch is only for use in battery backup mode and not for normal operation).
This is a redundant system and does not replace or substitute any requirements of UL 325
Interruption of Power for manual operation.
Assure used batteries are disposed of at the appropriate drop off center.
Emergency Open Operation:
Emergency Open (Battery Backup Test): pulling out the mushroom head switch located
on Emergency Hand Wheel enclosure will disconnect AC power to the motor and provide
DC battery power to automatically open the door. The mushroom head LED light will come
on indicating the operator is in emergency mode. Note: power entering this enclosure is
class 2 low-voltage.
With the Emergency Hand Wheel enclosure easily accessible to the technician, activation
will provide 2 benefits: (1) automatically opens the door in the event that any normal
functioning component (motor control, PLC, safety sensors, activation switches) has
malfunctioned; (2) provides a much easier method, then in the past, for performing periodic
Battery Backup Tests. In both cases, the end of travel limit switch will disconnect DC

power to stop the door in the open position. Pushing in the mushroom head switch will
reset the operator.
Sequence of events: pulling out the mushroom head E-stop* (see photo), removes power
to normally closed (N.C.) Relay 1** (providing DC power to the motor) and normally open
(N.O.) Relay 2** (disconnecting AC power to the motor control) and provides for
Emergency Open Operation or performs a Battery Backup Test.
Emergency Hand Wheel Manual Operation: opening the enclosure door will automatically
disconnect AC and DC power to the motor. This provides for safe and easy method of
testing the Emergency Hand Wheel Manual Operation without any danger of battery backup
activation caused by a possible power interruption while performing the test (fail-safe). In
addition, opening the door removes any resistance caused by the regenerative feature of
the motor drive. In the past, the 8 amp and 15 amp breakers inside the main panel needed
to be shutoff prior to performing this test.
Sequence of events: Opening the enclosure door (see photo), breaks the circuit to the
normally open (N.O.) limit switch*, disconnecting DC power to the motor and providing for
fail -safe operation of the Emergency Hand Wheel. At the same time, the circuit to the
normally open (N.O.) magnetic proximity switch* is broken, disconnecting power to the
(N.O.) Relay 2 and removing AC power to the motor control.
*Class 2 components added to Emergency Hand Wheel enclosure
**Relay 1 and Relay 2 have been added to the main control panel and replace the breaker switch formally used for Battery Backup tests

Installation Instructions
Although each Door Operator has been fully inspected and tested prior to shipment,
assure that no physical damage has occurred during shipping and handling. Premature
failure may occur if any part of the installation is not done properly.
To install the NB-4120-2-DC on bi-parting doors, refer to drawings NB-4120-2DC4 or NB-
4120-2DC-Travel. For single slide doors, refer to drawing NB-4120-2DC-SingleSlide-1.
1. Install 2 door attachments (lower belt)- refer to drawing NB-4120-2P2.
- Assure door attachments are level
- Create a centerline on the door attachment. Assure that it is
parallel with the track centerline within (+/-) 1/32”. (shim as
required)
- Use the centerline on the door attachment as your reference
dimension center line for the motor and take-up end brackets

2. Mount take-up end – refer to drawing NB-4120-2C4
- Verify take-up end is level
- Using the reference center line from the door attachments (from
step 1) assure the pulley is the same distance from the track
center line within
(+/-) 1/16”. (shim as required)
- Minor adjustments can be made by loosening the shaft collars,
loosening the set screws on take up bearings, and moving the
take up shaft from side to side

3. Mount motor end – refer to drawing NB-4120-2DC9
- Verify motor end is level
- Using the reference center line from the door attachments (from
step 1) assure the pulley is the same distance from the track
center line within
(+/-) 1/16”. (shim as required)

4. Mount timing belt
- Adjust take-up end pulley toward the motor end to allow for
maximum adjustment
- For Bi-parting doors, assure both doors are in the closed
position
- Attach one side of the 2” timing belt to the lower door
attachment closest to the take-up end, secure belt with clamping
plate and mounting hardware that was provided. Use torque
pattern while tightening
- Pull the belt through the take up end and around the pulley

- Pull the belt to the motor end and around the motor end pulley
while pulling out as much slack as possible (you may need to
use c-clamps to hold the belt to the pulley’s)
- Attach other end of the 2” timing belt to the lower door
attachment closest to the motor end, secure belt with clamping
plate and mounting hardware that was provided. Use torque
pattern while tightening (remove any c-clamps)

- Verify the belt teeth are fully engaged into their respective
pulleys. Adjust the take-up end threaded rods as required.
Adjust the motor end by shimming the bracket at the mounting
surface
5. Setting the belt tension – refer to parameter section of the 4120 Manual
- Belt tension is calculated and listed on a label on the motor end
bracket and inside the electrical panel
- Belt tension should be set with the belt idler engaged (about
3/8” into the belt)
- For single slide doors: measure the force it takes to deflect the
top belt 1” at the dead center of the belt between the pulleys,
use take up end to adjust accordingly
- For bi-parting doors: move the door to the open position then
set tension the same as a single slide door above
6. Install door attachment for upper belt– (Bi-parting Door only) refer to
drawing
NB-4120-2P2
- Move both doors back to the full closed position
- Assure door attachment is level and parallel with track
centerline within (+/-) 1/32”, using same center line dimension
from lower door attachments (shim as required)
- Assure clamping plate is engaged into the belt teeth and bolted
to the left door attachment (shim as required)

7. Install Emergency Hand Wheel – refer to drawing NB-4120-2DC8 and the
Instructions for installation (Emergency Hand wheel) below.
8. Pull the black cable harness with the 6 14-gauge wires into the
Emergency Hand wheel enclosure. Insert the 5 colored wires from the
pigtail into the matching colors labeled on the connector splice using the
insertion too supplied (attached to the wiring inside the enclosure)
Caution: To prevent risk of serious injury, assure source voltage has
been disconnected and all “lock-out” safety procedures have been strictly
adhered to.
9. Hookup 115 VAC supply voltage (230 VAC supply voltage for European
installations) and grounding per Terminal Strip Hookup, the applicable
Wiring Diagram, and/or local codes.
10. Connect 90-volt DC motor leads to the corresponding labeled wires (A1
and A2) on motor
11. Connect all Class (2) (24) VDC inputs per the Terminal Strip Hookup and the
Wiring diagram including required External Safety Devices (not included with
operator) that comply with the External Entrapment Protection of UL 325 for
Fail Safe Monitoring.
12. These devices can be door mounted, 4-wire reversing edge contact type
sensors that reverse the door while closing or compatible non-contact presence
sensors. Note: The door will not be allowed to close unless these sensors
are correctly wired per this manual. When installing contact type sensors,
assure they are properly secured to the leading edge of the door with sufficient