Borg Mechanical Digital BL5151SC – Knob Keypad and Lever Keypad Back-to-Back – Satin Chrome
The Borg BL5151SC is a fully mechanical digital lock in a unique back-to-back hybrid configuration: one side has a knob keypad (enter code, rotate knob to open) and the other side has a lever keypad (enter code, push lever down to open). Both sides have an independent coding chamber, so each side can be set to a different code if required. A code must be entered from whichever side you are on — there is no free egress from inside.
This configuration is well suited where each side of the door serves a different user group, where a space-saving knob profile is preferred on one side, or where a different code is needed for each direction of access. The lock uses the BL5000 series tumbler code system — code change requires removing the lock. Fire rated to AS 1905.1-2005 (up to 4 hours). Fully mechanical — no batteries. Suits doors 35mm to 54mm thick.
Usually same day if ordered before 11am AEST (excluding weekends and Qld public holidays)
The BL5151SC has a knob keypad on one face and a lever keypad on the other. Both sides have a full keypad with independent coding chambers. Each side can share one code, or be set to completely different codes. Operating sequence on the knob side: enter code, rotate knob to retract latch. Operating sequence on the lever side: enter code, push lever down to retract latch. A code must be entered on whichever side you are operating from.
Each keypad has its own independent coding chamber. Both sides can share the same code, or each side can be programmed to a completely different code. This means access from one direction does not give knowledge of the code for the other direction.
The inside (lever) keypad requires the correct PIN before the lever operates the latch. Confirm this suits your application and complies with any applicable fire egress or building regulations before purchasing.
Successfully tested up to 4 hours (depending on doorset) on fire door assemblies in accordance with AS 1905.1-2005 Fire Resistant Doorsets.
This model uses a tumbler-based code system. To change the PIN on either side, that side's keypad must be removed. Remove the 4 red screws, lift the cover plate carefully (springs attached), hold the C tumbler depressed, then use the supplied tweezers to reposition the red (coded) and blue (uncoded) tumblers. Over 8,000 combinations; code length adjustable from 3 to 7 digits. Each side is changed independently.
After entering the correct code and operating the lever or knob, press F to engage free passage mode on that side. To exit: operate the lever or knob and press C until an audible click is heard. Free passage can be engaged and exited independently per side. Deactivatable with the included plug.
Entirely mechanical. No power source, no wiring, and no battery maintenance at any point.
For heavy duty: consider the Borg BL7701, Lockwood DX, or Carbine CDL7000.
Each keypad accepts one active PIN code at a time. Each side can be set to a different code independently.
Key Features
- Unique hybrid back-to-back configuration – knob keypad on one side, lever keypad on the other.
- Independent coding chambers – each side can be set to a different code, or both sides can share the same code.
- Code required from both sides – no free egress from inside.
- Free passage function (F button) – independent per side; deactivatable.
- Tumbler code system – over 8,000 combinations; code length adjustable from 3 to 7 digits using spare tumblers.
- Fire rated to AS 1905.1-2005 (up to 4 hours depending on doorset).
- Fully mechanical – no batteries, no wiring, no power source.
- Clutch protection on both lever and knob – free-turning until correct code entered.
- 8mm square drive spindle – compatible with most leading lock brands.
- 60mm backset heavy duty tubular latch.
- Door thickness 35mm to 54mm (standard fixings).
- Satin chrome finish – suitable for internal use.
- Reversible on site for left or right hand doors.
What's in the Box
- Borg BL5151 knob keypad assembly (satin chrome)
- Borg BL5151 lever keypad assembly (satin chrome)
- 60mm heavy duty anti-thrust tubular latch
- Strike plate and box keep
- 2 × spindles (80mm and 90mm)
- M4 fixing screws (40mm, 50mm, 60mm options)
- 4 × 16mm screws
- 2 × coded tumblers (red – spare)
- 2 × non-coded tumblers (blue – spare)
- Tweezers (for code change)
- Hex wrench (Allen key)
- Handle screw rubber grommet × 2
Suitable Uses
- Internal doors where controlled access in both directions is required, and a different code per side is preferred or needed
- Applications where a compact knob profile is preferred on one side of the door (e.g. a corridor-facing side with limited clearance)
- Fire-rated internal door assemblies requiring both-sided code access control
- Doors where each direction of access is managed by a different user group with their own code
- Meeting rooms, server rooms, secure storage, and amenity doors requiring controlled both-sided access without batteries or wiring
Full Specifications
Dimensions
Frequently Asked Questions
Why does this lock have a knob on one side and a lever on the other?
The BL5151SC is specifically designed for applications where a different handle format is preferred or required on each side of the door. The knob side is more compact and can be useful where clearance is limited, or where a different user experience per direction is desired. The lever side provides a larger, easier-to-grip handle. Both sides have a full keypad and independent coding chambers, so each side can have its own code if required.
How do I change the PIN code?
The code must be changed with the relevant side's keypad removed from the door. Remove the 4 red screws, carefully lift the cover plate (springs are attached), hold the C tumbler depressed at all times, then use the supplied tweezers to reposition the red (coded) and blue (uncoded) tumblers for the new code. All square cut-outs must face outward and coloured marks must face upward. Each side is changed independently. Test the new code on that side before reinstalling.
Can each side have a different code?
Yes. Each keypad has its own independent coding chamber. To set different codes, change the tumblers in each side separately. Both sides can also share the same code if preferred — simply set both chambers to the same tumbler configuration.
How does free passage work on each side?
Enter the correct code on the relevant side and operate the handle, then press F while the handle is still engaged. That side's handle becomes free-turning. To exit free passage: operate the handle and press C until an audible click is heard. Free passage is independent on each side — engaging it on the knob side does not affect the lever side, and vice versa.
Which side should be the knob and which should be the lever?
There is no fixed rule. Typically the knob side is installed on the less-used or more space-constrained side, and the lever side on the primary access side. If one side is used more frequently or by people who may have difficulty gripping a knob, install the lever on that side. Handing of the latch itself is determined from the keypad side — right hand = hinges on right when viewing the knob keypad from outside.
Is this lock fire rated?
Yes. The BL5151SC is fire rated to AS 1905.1-2005 for use on fire door assemblies (up to 4 hours depending on the doorset). When specifying for a fire door, confirm all other hardware in the assembly (hinges, seals, closers) is also fire rated and compatible with the doorset certification. Also confirm that the BTB configuration (code required to exit from inside) complies with the emergency egress requirements for your specific fire door application.
Additional Information
For the tumbler code system, codes can be set on or off the door. It is strongly recommended to set and verify both side codes on the bench before installation. Set the knob side, test it, then set the lever side, test it. Only then install both sides to the door. This avoids the need to remove a fitted keypad for the first code change.
Two spindles are supplied (80mm and 90mm). Use the longest that fits. General rule: door thickness + 30mm = minimum spindle length (15mm must seat into each keypad). For a 45mm door, use the 80mm spindle minimum. Do not cut the spindle shorter than necessary. If too short, the spindle may disengage if the door is slammed, locking users out.
The BL5151SC BTB configuration requires code entry from inside. Confirm this complies with the emergency egress requirements for your specific fire door application before specifying. Both sides requiring code entry may conflict with escape route requirements in some occupancy classifications. Confirm with your fire door certifier or building surveyor.
All Borg locks are warranted against mechanical defects in materials and workmanship under normal use and service for a minimum of 12 months from date of sale. The warranty does not cover damage arising from misuse, vandalism, or improper installation. The lock must not be dismantled — doing so will invalidate the warranty.
What's In The Box – Borg BL5151SC
- Borg BL5151 knob keypad assembly (satin chrome)
- Borg BL5151 lever keypad assembly (satin chrome)
- 60mm heavy duty anti-thrust tubular latch
- Strike plate and box keep
- 2 × spindles (80mm and 90mm)
- M4 fixing screws (40mm, 50mm, 60mm options)
- 4 × 16mm screws
- 2 × coded tumblers (red – spare)
- 2 × non-coded tumblers (blue – spare)
- Tweezers (for code change)
- Hex wrench (Allen key)
- Handle screw rubber grommet × 2
Borg BL5151SC – Dimensions
Borg BL5000 Series – Product Brochure
Borg Locks Warranty – Australia
What is Covered
- Mechanical defects in materials and workmanship
- Defects arising under normal use and service conditions
- Repair or replacement of defective units at the discretion of the Australian distributor (LSC)
What is Not Covered
- Damage arising from misuse, vandalism, or abuse
- Damage resulting from improper installation
- Locks that have been dismantled — dismantling invalidates the warranty
- Normal wear and tear
- Cosmetic damage not affecting function
How a Warranty Claim Works
Warranty claims for Borg products in Australia are processed through LSC, the authorised Australian importer and distributor for Borg Locks. If the returned item is found by LSC to be defective, it will be repaired or replaced. Products must be returned to the LSC office with freight charges prepaid within the warranty period. A detailed assessment report is provided to the customer after examination.
Contact Terry’s Locksmiths first — we will assess the issue and manage the warranty process with LSC on your behalf. You do not need to contact LSC or Borg Locks UK directly.
Australian Consumer Law
Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure. The Borg manufacturer warranty above operates alongside — and does not limit — these statutory rights.
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