Electro-Voice 1252, 250 operation manual Dial-In Function, Dial-Out Function

2.4: INP2 Internal Modem with Dial-In/Dial-Out Option

2.4.1: Hardware Overview

The INP2 Option for the Nexus 1250/1252 meter provides a direct connection to a standard tele- phone line. No additional hardware is required to establish a communication connection between the meter and a remote computer. The RJ-11 Jack is on the face of the meter. A standard telephone RJ- 11 plug can connect the meter to a standard PSTN (Public Switched Telephone Network).

The modem operates at up to 56k baud. The modem supports both incoming calls (from a remote computer) and automatic dial-out calls when a defined event must be automatically reported.

With the device configured with the INP2 Option, the meter has dial-in capability and provides remote access to other Modbus-based serial devices via the meter’s RS-485 Gateway over your phone line. The meter will recognize and respond to a Modbus Address of 1. With any other address, the command will pass through the gateway and become a virtual connection between the Remote Modbus Master and any Modbus Slave connected to the RS-485 Gateway.

2.4.2: Dial-In Function

The modem continuously monitors the telephone line to detect an incoming call. When an incoming call is detected, the modem will wait a user-set number of rings and answer the call.

The modem can be programmed to check for a password on an incoming call. If the correct password is not provided the modem will hang up on the incoming call. If several unsuccessful incoming call attempts are received in a set time period, the modem will lock out future incoming calls for a user-set number of hours.

When an incoming call is successfully connected, the control of communications is passed to the calling software program. The modem will respond to computer commands to download data or other actions authorized by the meter passwords.

Refer to the Communicator EXT Software Manual for instructions on programming the modem.

2.4.3: Dial-Out Function

The Dial-Out Function (INP2) is intended to allow the meter to automatically report certain conditions without user intervention. The modem is normally polling the meter to determine if any abnormal or reportable conditions exist. The modem checks programmed meter conditions and programmed events (set in Nexus Communicator) to determine if a call should be placed.

If any of the monitored events exist, the modem will automatically initiate a call to a specified location to make a report or perform some other function. For log full conditions, the meter will automatically download the log(s) that are nearing the full state.

e Electro Industries/GaugeTech Doc # E107706 V1.25 2-3