Analyser Glass Break Detectors IU 400 Black

The IU 400 is an analyzer for the GD 475 glass break detector and connects to burglar alarm systems.

It has three relays, one for alarm, one for fault, and one for opening the cover or tampering with the unit. A maximum of 10 GD 475 units can be connected to one IU 400.

The IU 400 together with one or more GD 475 units have been tested and approved according to SBSC alarm class 3.

The IU 400 measures the current in a balanced loop without an end resistor, simplifying the connection of the detectors. You don't need to keep track of the end of a loop. It is the detectors together that form a balance under the control of the IU 400's processor. An end resistor of 2.2kohm is only needed if the number of detectors is 3 or fewer. When the current in the loop changes by +/- 0.8 mA for at least 200 ms, the alarm relay in the IU 400 opens for 2-3 seconds (AUT mode) or remains open (Latch mode) until reset, depending on how it has been programmed.

The loop in the IU 400 operates in the current range of 3 mA to 30 mA, corresponding to approximately 260 ohms to approximately 2600 ohms. Outside this range, the LED flashes, the alarm relay and the fault relay are open, and the unit cannot be reset or programmed.