Safety relay contact expansion modules

Pilz Automation Safety LP has introduced two new modules in the PNOZsigma range of slim line safety relays to enable the number of contacts to be expanded, offering the potential for savings in cost and space compared with traditional relays. The PNOZ s7.1 features three normally open safety contacts.

By Control Engineering Staff April 1, 2008

Pilz Automation Safety LP has introduced two new modules in the PNOZsigma range of slim line safety relays to enable the number of contacts to be expanded, offering the potential for savings in cost and space compared with traditional relays. The PNOZ s7.1 features three normally open safety contacts. It connects to a PNOZsigma base unit safety relay type PNOZ s1, s2, s3, s4, s5, s6, or s6.1. PNOZs7.1 incorporates a separate feedback loop that enables the 17.5-mm module to be used as a stand-alone safety relay. When a PNOZ s7.1 is used as a stand-alone unit or with a PNOZsigma base unit, further expansion is possible by connecting a maximum of ten PNOZs7.2 modules, each having four normally open safety contacts and one normally closed auxiliary contact. Or, a PNOZ s7.2 can be connected to a base unit as a single-expansion module. Although there is theoretically no limit to the number of PNOZ s7.1 expansion modules that can be used, each one adds 20 ms to the 50 ms reaction time of the base unit, according to the company. www.pilz.com Pilz Automation Safety L.P.