Drop indicator relay

Drop indicator relay for indicating danger and operating states

Drop indicator or annunciator relays are used as status indicators in control rooms, on control panels, and in mimic diagrams. Default contact assignments make rapid commissioning possible. That is why semi-automated or fully automated design variants feature clearly arranged display surfaces. Their robust design ensures reliable operation, even under harsh ambient conditions.

Drop indicator relay mounted in the control cabinet front

Your advantages Recognize system states at a glance

✔ Time-saving commissioning with preconfigured messages
✔ Reliable and durable operation with the robust construction
✔ Predefined contact assignments for numerous applications

How the drop indicator relays work Semi and fully automatic design versions

Semi and fully automatic drop indicator relays
Semi-automatic method of operation
Manual message acknowledgment with automatic reset of the indicator flag once the fault is remedied
Semi-automatic method of operation
Fully automatic method of operation
Automatic reset of the indicator flag once the fault is remedied without manual acknowledgement
Fully automatic method of operation
MR 11 annunciator relay flush-mounted version

Drop indicator relay with manual message acknowledgment

Semi-automatic drop indicator relays

The semi-automatic drop-indicator or annunciator relay MR 11 is used to display system states.
In this design version, message acknowledgment is performed manually by actuating the reset button mounted on the device front. This enables a clear overview of already known (acknowledged) or changed (not yet acknowledged) messages.
This allows service technicians on site to recognize whether system states are already known and whether appropriate measures have already been taken or whether measures still need to be taken. Upon acknowledgment and fault clearance, the drop indicator relay automatically returns to its original position.
The special feature of the semi-automatic design version is that the fault message on the front of the device is retained after fault clearance without prior message acknowledgment. This enables the service technician to recognize whether uninterrupted system operation was possible, even after the fault has been cleared automatically.

MR 21 annunciator relay flush-mounted version

Drop indicator relay with automatic message acknowledgment

Fully automatic drop indicator relays

The fully automatic drop indicator or annunciator relay MR 21 is also used to indicate dangerous states and operating states.
With this design version, message acknowledgment is automatic, without manual intervention. The device front therefore always displays the actual system state.
The fully automatic design version is therefore ideal for personnel-free system operations.

Flexible indicator flags for drop indicator relays

Marking labels Flexible messages for your system

The messages or indicator flags on the marking labels can be created individually to meet your requirements. Using preconfigured messages enables even faster commissioning.
The standardized plates also enable one or two-line printing, each with up to 15 characters.

The well-designed construction also enables the subsequent replacement of printed marking plates. They therefore remain flexible in use even after many years of operation.

Mounting methods Easy mounting in the control cabinet front or on the DIN rail

Overview of the drop indicator relay mounting methods
DIN rail mounting
A connector plate and clamp are required for mounting the relay on the DIN rail fastener (35 mm). These components can be found under Accessories.
DIN rail mounting
Front installation
A clamping frame and a touch-protection cap are required for mounting the relay in the control cabinet front or control panel front. The protective cap can be found under Accessories.
Front installation
Drop indicator relay combination housing

Combination housing for front installation

Combine drop indicator relays easily Ideal overview with front installation

Our combination housings allow you to easily mount up to nine drop indicator relays in the control cabinet front. The common carrier does not only simplify mounting, but also simplifies the overview of any messages present.
Depending on combination housing, up to four or up to nine drop indicator relays can be mounted. Naturally, you can also install fewer relays than the maximum. In this case, the remaining free slots are simply closed off with dummy plates. This means that you have the option of extending your system at a later date.