NEC nd-20292 manual Electra MARK11, Modem Termination, Installation

ND-20292

CHAPTER 2

APRIL, 1990

mode. Relay contacts (armature) for relays 4, 5, and 6 can be found at the MDF ECR 4A/4B through ECR 6A/6B. Relay contacts (armature) 7,8,9, and 10 can be found on the ECR-E ETU Al/B1 through A4/B4 connections CN 1 and CN2.

Connection information of the locally provided amplifier and speakers is provided in Figure 200-53. Audio output specifications can be found in Section 220.20 of this document.

It is not recommended to connect the locally provided amplifier directly to the ECR-E ETU relay contacts. These contacts are not designed to accept high level AC

signaling. Direct connection may also cause audio crosstalk between Single Line Telephone, outside lines and the tone ringing circuit.

270.5 MODEM TERMINATION

For Modem Pooling Connection, the following conditions must be complied with and the following equipment must also be made available:

A. The Electra Mark11 System must provide a Multiline Terminal (with DTA-E Unit installed) and an SLI-E( ) port to support each modem being installed.

B.Multiline Terminals with DTA-E Units installed (other than those connected to modems) for data

r----------------------- ---v-e.

communication with outside DTE (Data Terminal Equipment).

C.For supporting the DTA-E Unit, ESI-EB ETUs are required; to allow assignment of ESI-EB and SLI-E( 1ports for modem use, CPU-EB (or higher revision level) ETUs are required.

The Electra Mark11 System provides the data connecting paths and supports the control (setting and releasing) of the paths for data communication.

Protocol support or conversion is not supported.

Figure 200-54 shows the modem pool connections, the data path, DTE and other equipment required for modem pool operation.

INSTALLATION

NOTE: Prior to connecting the modem to the DTA-E Unit, ensure the modem is not powered.

A.Locate a modem near a Multiline Terminal (with a DTA-E Unit installed) already programmed for modem pooling.

B.Plug in the station line cord into the Multiline Terminal.

C.Plug the AC/DC adaptor into the nearest nominal 117i AC outlet. Connect the DC output cable of

LINE

,.-\, i

-..

./’

	ES-EB
	.----	-- I
MODEM		I
MULTILINE		I
TERMINAL	7 I		CPU-E()
WITH DTA-E		I	c
		I

DTEMULTILINE

TERMINAL

WITH DTA-E

ELECTRA MARK11

-

Figure 200-53 Modem Pooling Block Diagram

200 - 44