Digital Analog Tech Note 15 - TNDA15

Abstract

This document describes how to correct erratic counting when using a Red Lion counter.

Products

All Red Lion Counters

Problem

If you are experiencing erratic counting on your Red Lion Controls counter, more than likely what you are seeing is commonly called “chatter” on the input of the counter. The result of chatter is usually seen as excess counts being registered by the counter when it should have only received a single count from the input device. This chatter is usually caused by the natural bounce of a mechanical relay between the contacts and is detected by the counter because of the sensitivity of the input. Another common cause of this chatter can be electrical noise that can be transmitted to a DC line located too close to an AC line. Be sure your DC lines are separated from your AC lines by a minimum of 3 inches.

Corrective Action

Most Red Lion counters have built in filters that can be programmed in the unit to eliminate this problem. Others have separate inputs for low and high speed count rates, dip switches to adjust the amount of filtering, or a filter terminal that can be connected to the units common terminal to add the required filtering. Refer to the product data sheet or instruction manual to determine which type of filtering your unit has and how to adjust the desired amount of filtering. If your unit does not have built-in filtering, you should use an external filter prior to the input of the counter.

Disclaimer

It is the customer's responsibility to review the advice provided herein and its applicability to the system. Red Lion makes no representation about specific knowledge of the customer's system or the specific performance of the system. Red Lion is not responsible for any damage to equipment or connected systems. The use of this document is at your own risk. Red Lion standard product warranty applies.

For more information: http://www.redlion.net/support/policies-statements/warranty-statement