Important Notification: Telemecanique Emergency Stop Pushbutton Product Recall - Harmony Range

Our manufacturing plant has informed us that under extreme operating conditions, there is a potential risk of the malfunction of certain types of emergency stop buttons in our "Harmony" control & signaling range. The products in question are manufactured under the "Telemecanique" brand name, within the Harmony style 4 & 5 22mm diameter mounting product lines.

This risk occurs in cases where the operating head is subjected to extreme operating force. The result of which may cause the associated contact blocks to become detached. Should this occur, the button would not fulfill its cut-out function on subsequent operation. Although we consider the potential risk of injury to our users to be low, we have decided to recall the products affected as a precautionary measure.

All Harmony 22 mm diameter metal (ZB4-B...) and plastic (ZB5-A...) emergency stops heads, whether they are still in stock or already installed, are affected by this notice.

The following devices are not affected:

* Harmony style 5 (ZB5-B...) emergency stop heads when used in XAL-D/XAL-K control stations in conjunction with base mounted contact blocks.

* Spring return "mushroom" heads of type ZB4-BC... and ZB5-AC...

(Please note that it is not acceptable to use spring return heads for emergency stop functions)

Should you have products that are affected by this notice please implement the following procedure.

For products that have not yet been installed:

Immediately suspend sale and/or installation of these items and return them to us. The products in question will be exchanged free of charge with modified replacement products.

For products that have already been installed or assembled:

Perform an immediate visual inspection which can quickly verify the Emergency Stop assembly is still sound (see example below of contact block detached).

Until replacements have been made available, please ensure that all installed Emergency stop pushbuttons are operating correctly and are routinely inspected.

Complete the Product registration form, which documents the number of suspect E-Stops you have in your installation. Fax or email this form to us and we will ship replacements to you as soon as stock of modified product becomes available.

Upon receipt of the new E-Stop heads, replace them following the procedure shown in the photos at the end of this page. It is not necessary to disconnect the wiring of the pushbutton, as the head can be easily separated from the base. The replacement time of an operating head is estimated at 2 minutes per device. Although the change out of devices is a mechanical operation and does not involve the removal of electrical wiring, it does require access to the inside of a control station or cabinet. For this reason we recommend that the operation is conducted by or under the strict supervision of a licensed electrician.

The current operating heads will be replaced by modified heads bearing distinctive marking (raised ring), as shown in the following photograph, allowing for easy "front of panel" identification of old & new devices.
Our Thanks to:
Tony Moscioni

[This message has been edited by Bill Addiss (edited 12-21-2001).]