Yealink SIP T48U Manual

The Yealink SIP T48U is a high-end executive VoIP desktop phone featuring a 7-inch color touch screen, 12 programmable line keys, dual Gigabit Ethernet ports, integrated PoE support, HD audio with wideband codecs, Bluetooth and Wi-Fi compatibility, USB recording, and support for up to 16 SIP accounts. It is designed for business environments requiring advanced call handling, conferencing, and unified communications. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

Features at a Glance

Key components: 7-inch capacitive touch screen, Handset, Base unit, Ethernet cables, Power adapter, Quick start guide.

Installation

Unpack and inspect contents. Place on stable desk surface.

1. Connect to Network: Use Ethernet cable to connect LAN/PoE port to switch/router. For PoE, ensure switch supports 802.3af.
2. Connect PC: Use second Ethernet cable from PC port to computer for pass-through.
3. Connect Handset: Plug handset cord into dedicated port on base.
4. Power On: Use PoE or plug 12V DC power adapter into power port and wall outlet.

WARNING! Use only Yealink-provided or certified power adapter. Ensure proper ventilation.

First-Time Setup

Power on phone; follow on-screen prompts.

1. Select Language: Choose preferred language from initial setup screen.
2. Network Configuration: Phone will attempt DHCP. For static IP, configure via keypad or web interface.
3. Provisioning: Enter SIP server details manually or via auto-provisioning URL (from your service provider).
4. Account Registration: Enter SIP account credentials (username, password, server).
5. Test Call: Make a test call to verify audio and registration.

CAUTION! Keep phone away from liquids and extreme temperatures.

Specifications

• Display: 7-inch TFT LCD, capacitive touch, 800 x 480 resolution.
• Network: Dual 10/100/1000 Mbps Ethernet, IEEE 802.3af PoE.
• Protocols: SIP (RFC3261), TCP/IP, UDP, RTP, RTCP, HTTP/HTTPS.
• Audio Codecs: Opus, G.722, G.711 (A/µ-law), G.726, G.729, iLBC.
• Wireless: Bluetooth 3.0, optional Wi-Fi 802.11a/b/g/n.
• Power Supply: 12V DC, 1.5A or PoE (802.3af Class 2).
• Operating Temp: 0°C to 40°C (32°F to 104°F).
• Supported Services: Hold, transfer, forward, conferencing, call recording, XML push.

Controls and Settings

Access settings via touch screen or web interface (IP address). Front Panel: Touch screen, physical navigation keys, MUTE, HEADSET, SPEAKERPHONE.

Touch Screen: Home screen with call status, contacts, call history, settings shortcut.

Basic Settings: Language, time/date, ringtone, screen brightness. Network: DHCP/Static IP, VLAN, QoS. Account: SIP registration, caller ID, codec priority. Features: Call forward, DND, call waiting, auto-answer. Advanced: BLF, speed dial, XML applications, firmware upgrade.

Connecting Devices

Handset: Use included coiled cord. Headset: 3.5mm jack or Bluetooth pairing. Expansion Module: Connect via EXP port on back. PC: Ethernet pass-through via PC port.

1. Turn off phone before connecting wired accessories.
2. For Bluetooth headset: Enable Bluetooth in phone settings, put headset in pairing mode, select from phone list.
3. For Wi-Fi: Insert optional Wi-Fi module, configure SSID and security in network settings.

Tip: Use quality Ethernet cables for stable network connection.

Advanced Call Features

Supports advanced VoIP features for business use.

1. Call Hold/Resume: Press Hold key during active call.
2. Call Transfer: Press Transfer, enter target number, press Transfer again (blind) or wait for answer then transfer (attended).
3. Conference: During a call, press Conf, dial second party, press Conf again to merge.
4. Call Forward: Configure via settings (always, busy, no answer).
5. Speed Dial: Assign numbers to programmable keys for one-touch dialing.
6. BLF (Busy Lamp Field): Monitor status of colleagues' lines.
7. Call Recording: Press Record during call (requires USB storage).
8. Directory: Access local and LDAP contacts from touch screen.

WARNING! Do not disconnect during firmware upgrade. Ensure stable power.

Accessibility Features

Visual: Adjustable screen brightness, font size, contrast. Audio: Adjustable ring volume, tone, hearing aid compatible (HAC) handset. Physical: Large touch targets, tactile keys.

Care & Cleaning

Unplug power before cleaning. Use slightly damp, lint-free cloth for screen and body. Do not use abrasive cleaners or sprays.

CAUTION! Avoid moisture entering ports. Keep away from direct heat sources.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits for residential use. CE, RCM, UKCA marked. Hearing Aid Compatibility: Meets FCC HAC requirements. For support, visit www.yealink.com or contact your service provider. Copyright © Yealink Inc.

Troubleshooting

Reset: Press and hold OK key during boot for factory reset (use with caution).

Service: Contact service provider or visit www.yealink.com for firmware and documentation.