ESA 2/G JOLA alarm relay

Description

The ESA 2/G JOLA alarm relay is designed for limit level signalling (sensor 1) or for two-point monitoring (sensor 2). They shall be installed in a control cabinet or other suitable protective enclosure. The switches are suitable for use in clean environments.

Electronic alarm relay in a body housing, with transparent cover and two LEDs to indicate the corresponding switching status, inside the housing.

The design of the electrode alarm relay is based on the quiescent current principle, in other words, an alarm signal is given if there is no connection between terminals 11 and 12; the unit’s two potential-free output contacts also return to the alarm state if the supply voltage fails.

In standby mode (unit with voltage and connection between terminals 11 and 12), the potential-free switching output contacts are in the activated state and the two-colour LED is green.

In case of an alarm (unit energised and no connection between terminals 11 and 12), the potential-free switching output contacts are in an inactive state (contacts in a quiescent state) and the two-colour LED flashes red. An additional red flashing LED also flashes as a switching status indicator for the output relay, which can be acknowledged.

Output relay 1 (terminals 3, 4, 5) can be reset by connecting an external acknowledge button (connection option on terminals 9 and 10) to cancel the alarm emitted by this output. The red flashing LED then stops flashing and the two-colour LED returns to solid red.

ESA 2/G characteristics

• supply voltage: 230 V AC; on request: 240, 115, 24 V AC, 24, 12 V DC
• input power: approx. 3 VA
• electrode circuit: 2 terminals (under safety extra-low voltage SELV) operating on 2 output relays without self-checking (1 output relay can be reset if an alarm is activated)
• No-load voltage: 9 Veff 10 Hz (safety extra-low voltage SELV)
• short-circuit current: max. 0.5 mAeff
• response sensitivity: approx. 30 kW or approximately 33 µS (electrical conductivity)
• Control circuit: 2 potential-free normally closed contacts according to the quiescent current principle, both activated in standby mode. (more in the datasheet)
• Functionality: quiescent flow principle
• status indicators: two-colour LED green, red (see datasheet for details)
• switching voltage: max. 250 V AC
• switching current: max. 4 A AC
• switching power: max. 500 VA
• housing: insulating material, with three cable entries
• connection: internal terminals
• protection class: IP54
• installation: surface mounting with 4 screws
• orientation of installation: any
• temperature range: -20 °C to +60 °C
• length of connecting cable: max. 1,000 m between safety relay and sensor

For more information, please see the attached pdf documents under the Documentation tab.

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