• Cost-effective, compact monitoring of small machines without PLC, e.g. compressors.
• Modular design allows adjusting to plant extensions at any time (e.g. IL/SL 5990).
• Central monitoring of multiple PLCs or centralization of multiple alarm relays for an overall overview on machinery and plants.
• DOLD’s text fault annunciators can be programmed in several languages, e.g. for foreign operating personnel. Statistics stored in the text annunciator help to optimize the plant operation. The products can be extended by a two-wire bus system. Open-circuit monitoring within the bus system when configured according to the de-energized on trip principle.
• Prevent damages to man and machine in case of faults or even PLC failure.
• Avoid costly production losses by early fault detection and thus allow the implementation of an improved operational reliability.
• Reduce the time for troubleshooting by early and easy fault localization. Save time for fault finding.

Group fault, new-value and first-up annunciators have normally acoustic and visual indicators and are designed for DIN rail mounting or also for front panel mounting.

Group fault annunciators are available for 4 up to 160 signals and energize a relay when a fault signal occurs. Such a relay can be de-energized by an acknowledging key. A visual (flash lamp) or an acoustic (horn) transducer is connected to this relay output. New-value and first-up annunciators are used where the chronology of fault signals is essential.
The new-value annunciator signalizes that alarm among a number of alarms the status of which has changed last after the last acknowledgement. New-value annunciations are indicated by a flash lamp and after acknowldgement as permanent light until the fault is cleared.
The first-up annunciator signalizes that alarm among a number of alarms the status of which has changed first after the last acknowledgement. The first occurred fault is indicated by a flash lamp and consequential faults by permanent light.

Text fault annunciator systems

Text annunciator systems echo the correct sequence of the arrived fault signals. Stored alarms can be called up and viewed on the display. Text fault annunciator systems can be operated as new-value and also as first-up annunciators.
Text fault annunciators have outputs for group annunciation, horn and system readiness. Inputs and outputs are metallically isolated and thus ensure a maximum of interference immunity. Beyond standard applications, statistics, analog processing, time interrupt functions, decentralized acquisition and output as well as multilingualism of the fault texts are customer-specific options.
A printer can be used for logging, i.e. for printing date, time, test of the fault and the whole statistics memory of the system. With an appropriate programming software also other settings than message texts can be defined such as energized/de-energized-on-trip principle of inputs, delay of inputs as well as grouping and priority of outputs. A decentralized fault alarm acquisition in complex installations can be configured with up to 30 modules with 8, 16, 24 or 32 inputs each. Via a separate module, these modules are connected to a two-wire line which is connected to the central fault annunciator. A maximum of 957 fault alarms can be acquired with this. Additional remote control stations complete the system.

DOLD monitoring and measuring relays are used in all industrial areasand in a variety of applications. Some application examples for the differentdevice groups are mentioned below:

De-energized- versus energized-on-trip principle

DOLD fault annunciators are used to specify maintenance intervals for preventive maintenance and for general monitoring in following application areas (among others):

Industry:

• Production plants, production sequences and processes
• Machine functions, e.g. V-belt rupture, filter clogging, dry-running of pumps
• Compressors

Buildings:

• Heating, ventilation and air condition (HVAC)
• Doors, gates and windows
• Transport and materials handling systems

Environment:

• Power stations
• Sewage treatment plants
• Waste incinerating plants

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  Fault annunciator systems INFOMASTER, accessories