Avaya TN747B Definity PBX Expansion Card

Avaya TN747B Definity PBX Expansion Card Image 1

Avaya TN747B CO Trunk circuit pack for Definity and G3 PBX systems.

The Avaya TN747B is a Central Office (CO) Trunk circuit pack designed to provide analogue trunk connectivity between a PBX system and the public switched telephone network (PSTN). This card enables the connection of traditional analogue telephone lines to the switching system, handling incoming and outgoing calls via CO trunk circuits.

The TN747B is engineered for use within Avaya Definity and G3 series communication servers. It slots into the system’s universal card cage and provides multiple trunk ports for analogue line termination, supporting standard loop-start or ground-start signalling depending on configuration.

This is a legacy circuit pack from Avaya’s established Definity platform, which has been superseded by newer IP-based communication solutions. However, many organisations continue to operate Definity systems and require replacement or spare TN747B cards to maintain their existing infrastructure.

Available from Tech Star as new or refurbished stock. Submit a price enquiry for availability and lead time.

Frequently asked questions

Is the Avaya TN747B refurbished or new?
Tech-Star supplies both new and refurbished Avaya TN747B. Refurbished items are tested and graded against manufacturer specifications; the condition is confirmed at quote.
What warranty is included with the Avaya TN747B?
Refurbished Avaya TN747B comes with a 90-day parts and labour warranty as standard. Extended warranty options are available on request.
How do I get a price for the Avaya TN747B?
Pricing reflects current stock and lead time, so we quote per enquiry. Submit the part number through the contact form for a quote, typically within one business hour.
Can the Avaya TN747B be returned?
Returns are accepted within 14 days of delivery in line with our return policy. A restocking fee may apply for opened items.
How quickly can the Avaya TN747B be delivered?
Lead time depends on current stock. UK-based items typically ship the next business day; sourced items vary. We confirm lead time at quote.

Key FeaturesAnalogue CO trunk connectivity; Multiple trunk port capacity; Universal slot compatible; Loop-start and ground-start signalling support
ApplicationsPSTN line termination; Legacy PBX trunk expansion; Analogue trunk maintenance and spares
CompatibilityAvaya Definity systems; Avaya G3 communication servers
SpecificationsCO trunk interface; Analogue signalling; Standard TN-series form factor
PlatformAvaya Definity
ManufacturerAvaya

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