ZS 73 SR Belt Alignment Switch

• Metal enclosure
• 2 contacts
• Release by push button (VD) possible
• Belt-alignment roller made of stainless steel
• Indicator lamps for various voltages can be found in the chapter Accessories in the Appendix
• Indicator lamp position in the left side cable entry, other positions possible on request
• With 2 cable entries available on request
• Ex version available

Technical data

Applied standards	EN 60947-5-1, EN 60947-5-5, EN ISO 13849-1
Enclosure	aluminium die-cast, enamel finish
Cover	thermoplastic, glass-fibre reinforced, impact resistant, self-extinguishing UL 94 V-0
Degree of protection	IP 65 to IEC/EN 60529
B10d (10 % load)	ZS 73 SR VD: 200 000; ZS 73 SR: 2 million
TM	max. 20 years
Contact material	silver
Switching elements	1 NC/1 NO contact or 2 NC contacts, type Zb
Switching system	snap action, positive break NC contacts
Connection	screw connection terminals
Cable cross-section	max. 2.5 mm² (incl. conductor ferrules)

Cable entry	2 x M20 x 1.5
Rated impulse withstand voltage Uimp	6 kV
Rated insulation voltage Ui	400 V
Conventional thermal current Ithe	6 A
Utilisation category	AC-15
Rated operating current/voltage Ie/Ue	6 A/400 VAC
Short-circuit protection	6 A gG/gN fuse
Ambient temperature	–25 °C … +70 °C
Mechanical life	ZS 73 SR VD: > 100 000 operations; ZS 73 SR: > 1 million operations
Indicator lamp	as option
Approvals

Application

Range of application

Belt-alignment switches are suitable for applications with handling equipment. Here they are installed e.g. at both sides of a conveyor belt in order to monitor the misalignment of the belt.

Belt misalignment, evoked by for example not in the middle of conveyor belt positioned goods or pollution of track idlers and deflection pulleys, can lead without any monitoring measurements to damage, destruction, material covering and dropping.

Design and mode of operation

Belt alignment switches are actuated when the conveyor belt becomes misaligned. Depending on the plant arrangements, this signal can either be used to switch the equipment off or to provide automatic correction of the belt alignment. Thus they should be installed at both sides of the conveyor belt close to the deflection and drive pulleys. In case of very long conveyor systems further belt misalignment switches must be installed. Those are actuated with the misalignment of the conveyor belt. This signal can either switch the system off or start an automatic belt position correction, as well as at the same time generate an optical or acoustic indicating or warning signal.

All belt alignment switches have positive break NC contacts and those of series ZS also have a mechanical latching. At actuation the NC contacts are opened and latched mechanically. The release can either be carried by push button or key. Thus an unintentional, automatic restart of the conveyor belt is prevented.

All belt misalignment switches bear the CE mark according to the Low Voltage Directive 2014/35/EU.