Pre-installation of controllers, Required power for controllers, New installations – Larco Guardian II User Manual
Page 4: Previously installed electric strikes, Access controller, Installation guide
Access Controller
Installation Guide
Page 4 of 15
Pre-installation of controllers
Physical installation of the Guardian II controller can vary from site to site. The
are drawn full size to help you with the physical layout and installation of your new controllers.
Our controllers are truly "stand alone" devices. This means that once you supply power to the controller and
connect device (electronic strike, magnetic lock) wires, your system is ready to start up. The Guardian II controller
requires no wiring back to a central computer. All data is transferred between controllers and your PC computer,
via our rugged Admin and Export keys. It is good practice to mount your controller as close to the door strike as
possible, to minimize the wiring distance between the two devices.
Required power for controllers
Power required for the Guardian II controller is 9-12 VAC or VDC (0.3A). The maximum input voltage to the
controller is 12V.
Important: For AC supplies, a voltmeter should be used to
verify that the input voltage
DOES NOT exceed 12V
RMS.
New installations
Wiring diagrams for the Power Fail Lock and the Power Fail Unlock strike installations can be found on pages 8 &
9. The wires in the controller harness are color-coded. A 12 VDC electric strike (308-0045-000), available from
Larco, can be configured as a Power Fail Lock or Power Fail Unlock simply by re-positioning the two screws on the
side of the assembly. (Refer to Figures 1 & 2).
NOTE: The electric strike, as it is shipped from Larco (sold separately), will typically be set to "Power Fail Secure
(lock)" by the factory. Before installation of the strike, check to make sure that the strike is set to the mode you
require.
Figure 1
Figure 2
Fail Secure (Lock)
Fail Safe (Unlock)
A diode is integrated on-board the Guardian II printed circuit board to protect its relay. Refer to the
Previously installed electric strikes
The Guardian II controller operates (1) Form C, SPDT 2A@30VDC relay contact that acts as a switch for electric
strike or other device. If you have an electric strike installed, check to make sure that it does not exceed a
maximum current draw of 2 Amps @ 30 VDC resistive load.
If you are using a magnetic latch, check the voltage requirement and make sure that the current draw does not
exceed 2 amps. Some magnetic latches require a high voltage to operate. A separate power supply must be used
to power the magnetic latch only. In that case, refer to the wiring diagrams on