Linear BT125-W 825-11257 Dual-Technology Reader Technical Details
The Linear / Nice BT125-W 825-11257 combines Bluetooth Low Energy mobile access with 125 kHz proximity credential reading in one Wiegand reader. It is designed for new access-control installations and for existing systems transitioning gradually from physical cards and fobs to smartphone credentials.
The reader supports Linear Bluetooth mobile credentials while continuing to read most compatible HID, AWID, and Farpointe 125 kHz proximity credentials. Its included 2-in-1 mounting components allow installation on a narrow mullion, a standard single-gang box, or a suitable flat surface.
What the BT125-W Reader Does
When a supported physical or mobile credential is presented, the BT125-W reads the credential data and sends it to the connected access controller through Wiegand. The controller then checks the credential number, format, facility code, user record, schedules, access levels, and door permissions.
The access controller determines whether entry is granted. The BT125-W does not contain the cardholder database and does not provide a standalone lock or gate relay.
Supported Credential Technologies
- Linear Bluetooth mobile credentials using Bluetooth Low Energy
- Most compatible HID 125 kHz proximity cards and key fobs
- Most compatible AWID 125 kHz proximity cards and key fobs
- Most compatible Farpointe 125 kHz proximity cards and key fobs
- Industry-standard 26-bit Wiegand credentials
- Compatible custom Wiegand credential formats supported by the connected controller
Credential compatibility is determined by more than frequency. Verify the credential manufacturer, technology, bit format, facility code, card-number range, and access-controller configuration before ordering.
Linear Bluetooth Mobile Credential Support
The BT125-W works with the Linear Access Control Mobile App and separately purchased Linear mobile credential activation codes. The mobile credential is downloaded to a compatible smartphone and then enrolled into the access controller like a traditional card or fob.
- BT-MOB-L 830-00490: Standard-format Linear mobile credentials, sold in packs of 25
- BT-MOB-LC 830-0049C: Custom-format Linear mobile credentials, sold in packs of 25
The reader does not require a monthly subscription according to Nice/Linear. Mobile credentials must still be purchased separately, and the smartphone requires the current Linear Access Control Mobile App.
Compatible Linear 125 kHz Credentials
- ISO125-H 830-00400: Standard 26-bit HID-compatible ISO cards
- ISO125-HC 830-0040C: Custom-format HID-compatible ISO cards
- ISO125-A 830-00410: Standard AWID-compatible ISO cards
- ISO125-AC 830-0041C: Custom-format AWID-compatible ISO cards
- CLM125-H 830-00420: Standard 26-bit HID-compatible clamshell cards
- CLM125-HC 830-0042C: Custom-format HID-compatible clamshell cards
- CLM125-A 830-00430: Standard AWID-compatible clamshell cards
- CLM125-AC 830-0043C: Custom-format AWID-compatible clamshell cards
- KFB125-H 830-00440: Standard 26-bit HID-compatible key fobs
- KFB125-HC 830-0044C: Custom-format HID-compatible key fobs
- KFB125-A 830-00450: Standard AWID-compatible key fobs
- KFB125-AC 830-0045C: Custom-format AWID-compatible key fobs
This list identifies related Nice/Linear credentials. Confirm the required credential format and controller programming before ordering a credential batch.
Wiegand Reader-to-Controller Output
The BT125-W sends credential data to a compatible access-control panel through Wiegand. It supports industry-standard 26-bit Wiegand and compatible custom Wiegand formats.
Wiegand compatibility does not mean that every access panel will accept every credential. The controller must support the credential format, facility code, card-number range, and user capacity.
The reader does not provide a dry-contact access relay. A compatible access controller or standalone Wiegand controller is required to operate a gate input, electric strike, magnetic lock, door operator, or other controlled device.
Reader Wiring
- Red: Positive 8-14 VDC power
- Black: Ground
- Green: Wiegand Data 0
- White: Wiegand Data 1
- Brown: Access-panel-controlled LED input
- Blue: Beeper control
- Drain: Cable shield ground
- Unused conductors: Trim, isolate, and tape back according to the installation instructions
Apply positive voltage only to the red DC conductor. Follow the access-controller wiring diagram because LED and beeper control functions can vary by panel.
Power Requirements
The BT125-W operates from a power-limited 8-14 VDC source. Nice/Linear publishes a current draw of 60 mA typical and 120 mA peak.
The reader may be powered by a compatible access panel when the panel has adequate accessory capacity. Nice/Linear recommends a suitable Linear power supply for best operation, especially when troubleshooting reduced read range, electrical interference, or insufficient reader power.
Cable and Distance Requirements
- Runs under 300 feet: 24 AWG minimum, stranded multiconductor cable with an overall foil shield
- Runs from 300 to 500 feet: 22 AWG minimum, stranded multiconductor cable with an overall foil shield
- Published Wiegand maximum: 500 feet, subject to the access-controller manufacturer's requirements
Shield continuity should run from the reader to the access panel. The shield and reader ground should be tied together at the access panel and connected to earth ground at one point.
Do not share reader wiring with high-voltage conductors, gate motor wiring, variable-frequency drive wiring, or other circuits likely to introduce interference.
2-in-1 Mullion and Single-Gang Mounting
The BT125-W includes components for two common mounting arrangements:
- Mullion configuration: Narrow profile for metal door frames, window frames, posts, and other slim mounting surfaces
- Single-gang configuration: Wider plate for standard single-gang electrical boxes or suitable flat surfaces
Nice/Linear documentation states that mounting hardware and adapter plates are included. Use the supplied #6 screws or equivalent security fasteners approved for the mounting surface.
Physical Credential Read Range
The published physical-card and key-fob read range is up to approximately 3 inches. Actual range depends on the credential type, reader power, mounting surface, nearby metal, card orientation, electrical noise, and installation conditions.
A credential may have a higher standalone published range, but completed-system performance is limited by the reader and installation. Do not use the credential's maximum specification as a guaranteed BT125-W range.
Adjustable Bluetooth Range
Nice/Linear publishes adjustable Bluetooth range modes using a separate digital BLE range-setting control credential:
- Short range: Up to approximately 2 inches
- Medium range: Up to approximately 10 inches
- Long range: Up to approximately 15 feet
- Maximum range: Up to approximately 30 feet
The range-setting guide identifies the 15-foot mode as the factory default. Actual smartphone range varies with the phone model, case, BLE signal strength, credential configuration, approach direction, and environmental conditions.
Adjusting Bluetooth range does not change the reader's 125 kHz physical credential range. The BLE range-setting credential is separate and is not confirmed as included with the reader.
Indoor and Outdoor Installation
The BT125-W is IP67 rated for indoor and outdoor installations. Its electronics are sealed in weather- and tamper-resistant epoxy potting.
IP67 does not make the entire wall box, cable entry, splice, conduit, or mounting surface waterproof. Outdoor installations still require properly sealed cable penetrations, suitable wiring methods, drainage, corrosion-resistant hardware, and an appropriate enclosure for field splices.
LED and Audio Indication
The BT125-W uses a blue idle/status LED and an audio beeper. Presenting a supported credential causes the reader to beep and flash. The access panel can control the accepted-access LED indication through the reader control conductor.
A beep and flash confirm that the reader detected a credential. They do not by themselves prove that the access controller accepted the credential or activated its relay.
Important Controller Compatibility Warning
Before replacing an existing reader, verify:
- Reader supply voltage
- Available current capacity
- Wiegand Data 0 and Data 1 interface
- Credential frequency and technology
- 26-bit or custom credential format
- Facility code and card-number range
- LED and beeper control wiring
- Cable gauge, shielding, and distance
- Mounting footprint and wall-box configuration
A similar-looking reader using OSDP, clock-and-data, RS-485, proprietary serial communication, 13.56 MHz smart credentials, or another voltage is not automatically interchangeable.
BT125-W Compared With Similar Nice/Linear Readers
- BT125-W 825-11257: Bluetooth mobile credentials plus HID, AWID, and Farpointe-compatible 125 kHz proximity credentials with Wiegand output.
- BT135-W 825-11357: Bluetooth mobile credentials plus Linear 13.56 MHz DESFire smart cards and fobs with Wiegand output.
- NBT125-W: 125 kHz physical credential reader without the BT125-W mobile credential feature.
Similar Products That Are Not Automatically Interchangeable
- Linear BT135-W 13.56 MHz smart-card reader
- Linear NBT125-W non-Bluetooth reader
- OSDP readers using RS-485 communication
- Readers requiring 12 VAC or another supply voltage
- Readers with a built-in standalone relay
- Readers using proprietary credential formats
- Bluetooth readers from another mobile credential platform
- Long-range vehicle readers
- Gate radio receivers for handheld transmitters
Features and Specifications
| Specification | Details |
| Brand | Linear / Nice |
| Model | BT125-W |
| Part Number | 825-11257 |
| Product Type | Bluetooth and 125 kHz proximity access-control reader |
| Bluetooth Technology | Bluetooth Low Energy at 2.4 GHz |
| Physical Credential Frequency | 125 kHz |
| Supported Physical Credential Families | Most compatible HID, AWID, and Farpointe proximity cards and fobs |
| Mobile Credentials | Linear Bluetooth mobile credentials |
| Reader Output | Wiegand Data 0 and Data 1 |
| Supported Formats | Industry-standard 26-bit and compatible custom Wiegand formats |
| Operating Voltage | 8-14 VDC power-limited source |
| Current Draw | 60 mA typical, 120 mA peak |
| Physical Credential Read Range | Up to approximately 3 inches |
| Published BLE Range Modes | Up to 2 inches, 10 inches, 15 feet, or 30 feet |
| Factory-Default BLE Setting | Up to approximately 15 feet according to the range-setting guide |
| Mounting Configurations | Mullion, single-gang box, or suitable flat surface |
| Mullion Dimensions | 1.48 inches wide x 4.74 inches high x 0.54 inch deep |
| Single-Gang Dimensions | 2.99 inches wide x 4.74 inches high x 0.54 inch deep |
| Cable Under 300 Feet | 24 AWG minimum, stranded multiconductor with overall foil shield |
| Cable From 300 to 500 Feet | 22 AWG minimum, stranded multiconductor with overall foil shield |
| Maximum Published Wiegand Distance | 500 feet, subject to controller requirements |
| Environmental Rating | IP67 for indoor and outdoor installation |
| Electronics Protection | Weather- and tamper-resistant epoxy potting |
| Operating Temperature | -40 F to 149 F on the current product page; verify current product label |
| Operating Humidity | 0% to 90% relative humidity in the published installation documentation |
| LED Indicators | Blue status LED with access-panel-controlled green indication |
| Audio Beeper | Included |
| Monthly Reader Subscription | None stated by Nice/Linear |
| Manufacturer Warranty | Limited lifetime |
Package Contents
- One Linear / Nice BT125-W reader
- Slim mullion mounting components
- Single-gang mounting components and adapter plate
- Mounting screws and installation hardware
- Product installation documentation as packaged by the manufacturer
Verify the current box contents before publishing. Linear mobile credentials, physical cards or fobs, reader cable, power supply, access controller, BLE range-setting credential, controlled hardware, and installation labor are separate.
Required but Not Included
- Compatible Wiegand access controller
- Power-limited 8-14 VDC source with adequate current capacity
- Shielded stranded multiconductor reader cable
- Linear mobile credential activations or compatible 125 kHz credentials
- Linear Access Control Mobile App for mobile credential users
- Electric strike, magnetic lock, gate interface relay, or other controlled hardware
- Request-to-exit and free-egress equipment where required
- Emergency release, fire access, and mechanical override equipment where required
- Weatherproof splice enclosure, conduit, and sealing materials for outdoor work
Technician Troubleshooting Notes
If the reader powers up but has short range or does not recognize a credential, check the following before replacing it:
- Correct 8-14 VDC voltage at the reader under load
- Adequate current capacity, with 12 VDC recommended in the troubleshooting guide
- Correct cable gauge and total cable distance
- Proper shield continuity and single-point grounding
- Supported credential technology and format
- Nearby metal or electrical interference
- Reader Data 0 and Data 1 wiring
- Access-panel programming and credential enrollment
A credential beep with no door or gate operation usually indicates that the reader detected the credential but the controller did not authorize it, did not receive valid Wiegand data, or did not activate its output relay.
Before Ordering Checklist
- Confirm model BT125-W and part number 825-11257.
- Verify that Bluetooth mobile access and 125 kHz proximity are both required.
- Confirm that the access controller accepts Wiegand input.
- Verify standard 26-bit or required custom credential format.
- Confirm the facility code and credential-number range.
- Check for duplicate credentials in the existing database.
- Verify an 8-14 VDC power-limited source with at least 120 mA peak capacity.
- Measure the reader cable distance and select the correct wire gauge.
- Confirm mullion, single-gang, or flat-surface mounting.
- Verify that mobile credentials or physical credentials are ordered separately.
- Confirm the desired BLE detection range and availability of the range-setting credential.
- Verify outdoor conduit, sealing, grounding, and splice requirements.
Installation and Professional Advisory
Installation and wiring should follow the current Nice/Linear instructions, the access-controller manual, NFPA 70, and applicable local codes. Connect the reader only to a power-limited DC source. Do not connect it to a receptacle controlled by a switch.
A qualified access-control or low-voltage technician should complete the installation when reader power, Wiegand wiring, grounding, credential format, outdoor sealing, or controller programming is unclear.
Do not connect the reader directly to line voltage or substitute it for an access controller. Do not bypass free-egress hardware, emergency release, fire access, mechanical override, gate safety devices, or other required life-safety provisions.
Product Questions & Answers
What is included with the Linear BT125-W 825-11257 reader?
The package includes the BT125-W reader plus mullion and single-gang mounting components, adapter hardware, and mounting screws. Mobile credentials, physical cards or fobs, reader cable, power supply, and access controller are separate.
Which physical credentials can the BT125-W read?
The BT125-W reads most compatible HID, AWID, and Farpointe 125 kHz proximity cards and key fobs. Verify the credential format, facility code, card-number range, and controller support before ordering.
Are Linear Bluetooth mobile credentials included with the reader?
No. Linear mobile credentials are purchased separately as BT-MOB-L standard-format or BT-MOB-LC custom-format activation packages, and users need the Linear Access Control Mobile App.
Can the BT125-W connect directly to a gate operator or electric lock?
Not normally. The BT125-W outputs Wiegand credential data and does not provide a standalone dry-contact relay. A compatible access controller is required to authorize the credential and operate the gate or lock relay.
What power does the BT125-W require?
The reader requires a power-limited 8-14 VDC source. Nice/Linear publishes a current draw of 60 mA typical and 120 mA peak.
How can the BT125-W be mounted?
The included 2-in-1 hardware supports slim mullion mounting and standard single-gang mounting. The reader can also be installed on a suitable flat surface using the correct hardware and wiring method.
What are the physical and Bluetooth read ranges?
Physical 125 kHz credentials are rated up to approximately 3 inches. Published BLE modes range from about 2 inches to 30 feet, but actual smartphone range varies with the phone, case, signal strength, mounting, and site conditions.
What is the difference between BT125-W and BT135-W?
BT125-W reads Linear Bluetooth mobile credentials and compatible 125 kHz HID, AWID, and Farpointe proximity credentials. BT135-W uses Linear Bluetooth mobile credentials and Linear 13.56 MHz DESFire smart cards and fobs.
