GWZ-S2.1 / GWZ-S4.1

Connection with up to four sensors and two digital inputs

Depending on the configuration up to 4 sensors out of the product range can be connected to the 4..20 mA interface. The sensors are supplied via this device with 24 V DC. There is also a digital input for to wire a digital signal contact (e.g. pressure, water level) and a digital input for the external horn reset.

Relay outputs with test function for alarm, horn and malfunction

The limit monitor has 4 potential-free relay outputs, which are configured as follows:

• Up to 4 alarm relay: The relay contacts report an exceeding or falling below the threshold limits. So, for example, they can visually and acoustically trigger pre and main alarm or start-and turn off a fan again. The alarm outputs are available with hysteresis, latching or latching prematurely acknowledged. The alarm relay can be assigned a time function (minimum pulse time, maximum pulse time, delayed on/off).
• 1 x Horn relay to control a horn
• 1 x fault alarm relay: While the limit monitor keeps a watch on cable break, short circuit, and electronic failure, the fault message relay system displays malfunctions.
  A test function allows the verification of the output relay.

Control unit with display and status indicator

Via an alpha-numeric display the concentration values of the connected sensors are shown on a rolling basis. Additional status LEDs display information about the operating status, malfunction, horn and alarms.

Configurable on the device or via PC interface

The device can be either configured directly via button and display or being connected by an RS232 interface to a PC. By using the configuration software the device can be easily configured via PC.
At the limit monitor the following parameters and settings can be programmed for each sensor individually (via button or PC interface):
The limits, the final measuring range value, the unit of measure (LEL, ppm, vol%, °C, etc.), alarms (made either when exceeding or falling below the limit) and alarm output (optionally being stored, not stored or carried as an impulse).

Suitable for wall mounting

The limit monitor is available in a waterproof housing (IP65) for wall mounting free to choose between 24 V DC and 230 V AC supply voltage.

Configurable data logger

With the configurable internal data logger the data of each sensor connected can be recorded and be read again via the PC interface.

Self-monitoring with fault detection for cable break, short circuit and power failure

The device is self- monitoring the wiring of the sensor. It detects wire break and short circuit while triggering a fault message. The malfunction alarm relay is designed fail-safe, means, in case of failure power supply is cut off (closed-circuit principle) and a power failure can thus be detected.

"Inhibit" mode of operation

The "Inhibit" feature allows freezing the relay status for more than 20 minutes. This prevents from triggering the alarm during maintenance.

Certifications

The limit monitors meet the following directives and standards:

• EMC Directive 2014/30/EC and the standards DIN EN 50270:2007-05, DIN EN 61000-6-2:2006-03 and DIN EN 61000-6-3:2007-09
• Low Voltage Directive 2014/35/EC and the standard EN 61010-1:2011.

Maintenance and Service

The device itself is maintenance free. We recommend regular maintenance for the connected sensors. For this purpose we offer a test gas suitcase or you send the probes to us. Please contact our service center.

General

Connectors

Display and Operation

Pin assignment

In the product version GWZ-S2.1, the terminals 19 to 24 are not present. All relays are marked in non-operating state.