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Avaya 8400B Plus Data Service Unit

(£84.00 inc tax)
  • 8400
Product Code:
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The Avaya Avaya 8400B Plus Data Service Unit (product code: 8400B) is a full duplex asynchronous data module that provides desktop integrated voice-data communications via twisted-pair wiring.

The 8400B works with the two-wire Definity Digital Communications Protocols Circuits. It replaces (and is compatible with) the 7400B Plus Data Module.

The Avaya 8400B is available from MF Communications, fully tested and with a one-year warranty.

MF Communications stock a complete range of Avaya 8XXX Series business phones and phone accessories including:

8434DX IP Phone 

8510 IP Phone 

8410D IP Phone 

26B1 Key Module 

CallMaster V 

IP PSU 1151B1

Key Features

  • Non-volatile, read-write memory for storing installation options, two data options profiles, and up to four telephone numbers
  • An AT command interface that emulates a Hayes 2400 Smartmodem and supports the following:
  • storage of the wait time for carrier detect interval (S-register S7)
  • voice call origination using the ATDP command
  • Automatic speed and parity adjustment
  • Even, odd, mark, space or no parity
  • Automatic data throughput adjustment
  • Power-up self-test
  • Local and remote loopback tests with test duration timers
  • Voice terminal powered by the PBX is not affected if AC power is removed from the 8400B Plus Data Module

At MF Communications we offer a full one year warranty* on all new, remanufactured and refurbished products.

We offer after sales support** and advice from answering simple user questions to full system programming services. These services are maintained through a combination of online support documents and a full range of business telecoms services, including our maintenance and support services.

We will do all we can to offer our assistance with any problems you may encounter.

MF Communications has built its reputation on offering customer satisfaction. So if you are a customer with a problem, we want to know about it. You can contact us by calling +44 (0) 1892 514687 or email

*some DECT telephones & untested equipment has a reduced time period warranty.

**where relevant to products/services offered.

UK Delivery

We aim for next day delivery. Any order placed before 1.00 pm on any business day (Monday - Friday excluding Bank Holidays) should be delivered the next business day before 5.30 pm (assuming the item is in stock).

Worldwide Delivery

We ship worldwide from our UK warehouse. All international shipment charges are quoted per parcel. If your order exceeds the standard parcel size further shipment charges will be due before the order can be shipped. We will contact you directly with any additional shipment charges are due.

Read more information on UK and Worldwide Delivery.

  1. The Customer is required to inspect all goods upon receipt and to notify MF Communications Limited of any defects or complaints within 7 days of receiving goods.
  2. It is the responsibility of the customer to ensure the safe return of faulty or incorrect goods to MF Communications Limited.
  3. All goods returned must clearly state customers name, order no, telephone number, fault details and proof of purchasing. These goods must be in MF Communications Limited’s original packaging and condition, with original insertions, fixtures and parts. Failure to do so will result in the refund being invalidated.
  4. We use tamper proof labels which are stuck to each item sold by MF Communications Limited. This ensures that goods have been purchased from MF Communications Limited. When the label is peeled back MF Communications Limited Company details sticks to the glue and the label will then say void. No goods will be accepted back unless this label is intact.
  5. Restocking Fee 20% UK Only. Returned Goods MUST be in re-saleable condition or customer will be charged full invoice value.
Aastra Dialog 4425 IP V1

End of life product support: Professional and Competent

At MF Communications, we understand there are many reasons to keep an end-of-life system in operation. Our quality remanufacturing and refurbishing process ensures we are able to supply parts, spares and phones you can rely on to keep your system in operation for as long as you need it to.

We have been supplying new, remanufactured and refurbished business phones, telephone systems and parts since August 2000. We have built a strong reputation for high-quality products, support and excellent customer service to businesses in over 125 countries.

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