Spectrum Controls 1771sc-IMI16 User Manual

Publication 0300125-02 Rev. B

Isolated AC/DC (22O/24O V) Input Module
16 Discrete Inputs
Cat. No. 1771sc-IMI16

Installation Data

To the Installer This document provides information on:

• important pre-installation considerations

• power supply requirements

• installing the module

• using the indicators for troubleshooting

• module specifications

Throughout this document, we use the following symbol to make you aware
of safety considerations:

This symbol identifies information about practices or circumstances that can lead

!

Please read all the information in this document before installing the product.
This document assumes a full working knowledge of the relevant PLC.

to equipment damage, personal injury, or death. This symbol helps you identify
a hazard, avoid the hazard, and recognize the consequences.

Installation Data

AC/DC (220/240 V) Input Module
Cat. No. 1771sc-IMI16

Important Pre-Installation
Considerations This module must be used with a 1771 Series B (or later) I/O chassis.

This module contains input filtering to limit the effects of voltage transients
caused by contact bounce and/or radiated electrical noise. This filtering cannot
be turned off. The delay due to filtering is:

• Off to On 11 ± 6 ms for AC
3 ± 2 ms for DC

• On to Off 29 ± 8 ms for AC
30 ± 7 ms for DC

This module is designed to operate with input devices such as limit switches,
float switches, selector switches, push-buttons, and proximity switches. A
simplified schematic for this module appears in Figure 1.

Figure 1
Simplified Schematic

1771

Backplane

System

Circuitry

(filtering)

56.2 k½

Opto

Isolation

250 ½

0.15 µf

AC High

or DC Positive

Input

Indication

LED

56.2 k½
AC Low

or DC Common

The module is shipped in a static-shielded container to guard against electrostatic
discharge damage. Observe the following precautions when handling the module:

CAUTION

!

ELECTROSTATICALLY SENSITIVE COMPONENTS

Observe the following precautions to guard against electrostatic damage:

¥ Wear an approved wrist strap grounding device, or touch a grounded

object to discharge yourself before handling the module.

¥ Do not touch the gold backplane connector or connector pins.

¥ If available, use a static-free work station.

¥ Keep the module in a static-shielded bag when not in use or during

shipment.

Failure to observe these precautions can degrade performance or damage the
module.

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Installation Data

AC/DC (220/240 V) Input Module
Cat. No. 1771sc-IMI16

Power Supply Requirements Your module receives its power from the chassis power supply through the

1771 I/0 chassis backplane. The module requires 100 mA, maximum, from the
output of this supply. Add this to the requirements of all other modules in the
I/O chassis to prevent overloading of the chassis backplane and/or backplane
power supply.

Installing The Module In this section, we tell you how to key your I/O chassis, install your module,

and connect your wiring.

Keying Your I/O Chassis

Use the plastic keying bands, shipped with each I/O chassis, to key the I/O slots
to accept only this type of module.

The module circuit board is slotted in three places on the rear edge. The position
of the keying bands on the backplane connector must correspond to these slots
in order to insert your module. You can key any connector in an I/0 chassis to
receive this module except for the left-most connector, which is reserved for
adapter or processor modules.

Place keying bands between the following numbers labeled on the backplane
connector:

• Between 2 and 4

• Between 12 and 14

You can change the position of these keys if system redesign and rewiring
makes inserting a different module necessary.

Installing The Module In Your Chassis

To install the 1771sc-IMI16 in your 1771 I/0 chassis, follow these steps:

WARNING

!

POSSIBLE EQUIPMENT DAMAGE AND OPERATION

Always remove power from the 1771 I/0 chassis backplane and wiring arm
before removing or installing an I/O module.

¥ Failure to remove power from the backplane or wiring arm can cause module

damage, degraded performance, or injury.

¥ Failure to remove power from the backplane can also cause injury or equipment

damage due to possible unexpected operation.

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