Siemens GRD121.1U Electronic Damper Actuator,
The direct coupled, fast-acting, two-position, spring return
electronic actuators are available as 24 Vac/dc, 120 Vac,
and 230 Vac models. They are intende for use on
UL-listed smoke control and combination fire/smoke
rated dampers.
Applications
The GRD Series Spring Return Fire and Smoke Damper
Actuator is use for the control of dampers requiring up to
30 lb-in driving torque. It is intende for control of UL listed
smoke control dampers or combination fire/smoke HVAC
dampers. This actuator is designe to meet the 2002
revisions to the UL 555/555S and the AMCA Standard 520
applications.

