DRAGOset for Limit Alarm Switch DG 35200

DRAGOset for DG 35200

The confi­gu­rable Limit Alarm Switch DG 35200 is used for limit moni­to­ring and pro­cessing of uni­polar and bi­polar standard signals. A SPST relay or optio­nally an iso­la­ted, passive tran­sistor switch (Open-Collec­tor) is available at the output.

Settings of the limit switch

Input settings


In the Input section select the signal that you want to connect to the measurement input.

For the measuring ranges 0 ... 20 mA, 0 ... 10 mA, 0 ... 10 V and 0 .. 5 V, live zero and bipolar ranges and an absolute value range are also available.

In the measuring range 4 ... 20 mA, NE43, the measuring range limits according to NAMUR recommendation NE43 are also monitored in addition to the switching points.

Trip points and hysteresis
Setting trip points and hysteresis


The limit alarm switch controls up to 2 switching points: MIN alarm, MAX alarm or range monitoring with MIN and MAX alarm. Accordingly, the setpoint inputs are also enabled.

By selecting the unit, the trip points and hysteresis can be entered in % of the measuring range or directly in the measured variable mA or V.

The graphic visualizes the trip points and the hysteresis and calculates the switching point limits.

Measuring range monitoring
Measuring range monitoring


To monitor the limits of the selected measuring range, there are convenient setting options in the menu. Select a range monitoring and DRAGOset automatically sets the parameters to the range.



Example range 4 ... 20 mA:

Measuring range MIN = 4.0 mA (0 %) MAX = 20.0 mA (100 %)
Extended measuring range    MIN = 3.8 mA (-1.3 %)    MAX = 20.5 mA (103.1 %)
NAMUR error limits MIN = 3.6 mA (-2.5 %) MAX = 21.0 mA (106.2 %)


Switching delay
Switching characteristics

The switching behaviour of the alarm output can be set here:

Default The output reacts immediately
ON delay The output reacts after the delay time
OFF delay The output remains active for the delay time
Confirmation mode   The output remains active until the alarm is confirmed.
The confirmation is made via the externally connected reset switch.
Wiper contact The output is only active for the set time, then it becomes inactive, even if the cause has not yet been eliminated. To reactivate, the input must first reach the switch-off value, only then can the wiping contact be reactivated.
Extended ... In this setting, all times can be set individually:


Set extended time behaviour

ON delay:
After the trip point has the alarm been activated, the delay time elapses until the output is activated. If the input is inactive within this time, the alarm will be rejected, if necessary the delay time will start again.

OFF delay:
The input enters an inactive area and the alarm becomes inactive, then the delay time elapses before the output also becomes inactive. If the switch-off delay is set to -0.1 s, the delay is infinite. Only an confimation signal via an externally connected reset button resets the alarm.

Minimum ON time:
An alarm will be increased if the duration is less than the minimum activation time. This makes it reliably possible to detect short output peaks.

Maximum ON time:
After the maximum time has elapsed, the output becomes inactive even though the alarm status at the input is still present.

Alarm and working direction
Set alarm and working direction


With the alarm setting you can choose between MIN, MAX and MIN/MAX limit value monitoring. In the graphic you can see how this affects the output.

In the working direction, select whether you want to use a normally open contact (closed if alarm is active) or a normally closed contact (open if the alarm is active). The normally closed contact is only simulated by the device, i.e. the contact opens if the supply voltage fails.

Teach-in mode

The trip point can be teached-in and corrected during operation with the front-side teach-in push-buttons:

Trip point
In this mode, pressing one of the TeachIN buttons for at least 3 seconds until the blue LED lights up, the actual input measurement value is stored as the trip point at this time. The hysteresis remains unchanged, it has been defined either via DIP switches or via the configuration interface.

MIN/MAX limits
In this mode, the switch-on point and the switch-off point are set via teach-in. Simulate the measured value for the trip point at the input. Press the upper teach-in button for at least 3 seconds until the blue LEDs light up, the actual input measurement value is stored as the trip point. Then the lower blue LED flashes to indicate that the switch-off point still has to be entered. Simulate the measured value for the switch-off point at the input. Press the lower teach-in button for at least 3 seconds until the blue LED lights up, the desired hysteresis is calculated and stored from the trip point and the actual input measurement value.

Fine adjust the trip point
In all modes, the trip point can be easily readjusted. To do this, briefly press the upper key for "Increase trip point" or the lower key for "Decrease trip point", the keystroke is registered with a short blue flash. The trip point is changed by 0.5 % in each case. As an indication, the respective blue LED glows.
If you correct the trip point in the opposite direction again, the blue LEDs turn off when the adjust correction is set to ±0.


Message output
Settings for message output

The message output activates a collective message on the In-Rail-Bus in the DIN rail. In the dialog box, you can select the device messages that are enabled to activate the collective alarm.

By default, the collective alarm is not dependent on measured values.

Input error The input signal overrides the input and cannot be measured.
Measuring range The set measuring range is exceeded or undershot.
Alarm active The alarm is active, e.g. limit value MAX exceeded (immediately without delay times)
Output active The output relay is activated due to an alarm, the delay times have elapsed.
No supply Without supply voltage, the collective alarm is always activated.
Short transmitter supply The transmitter power supply is short-circuited, possibly is a wrong wiring or sensor fault.
Device error The device software has triggered an internal error.
Configuration error   Error in the set parameters, please check your programming.

The collective alarm can be provided with a switch-on delay to suppress short events. The delay time is set to 0.5 s when delivered.

With the minimum switch-on time, short collective alarms can be extended. At delivery, the time is set to 0.5 s.

DIP Switches
Settings with DIP switches

DRAGOset er­mittelt aus Ihren Ein­ga­ben die rich­tige DIP-Schal­ter-Pro­grammie­rung. Dieses Bild finden Sie auch in der PDF-Do­ku­men­ta­tion und im Aus­druck wieder.

Wenn Sie DRAGOset nicht mit dem Kabel mit dem Gerät ver­bunden haben, können Sie diese Pro­gram­mie­rung manuell auf die DIP-Schal­ter des Mess­um­for­mers über­tra­gen. Mit den DIP-Schaltern sind nur aus­ge­wählte Stan­dard­ein­stellun­gen möglich.

Wenn Ihre Kon­fi­gu­ra­tion nicht als Stan­dard-Ein­stellung ver­füg­bar ist, können Sie die Ein­stellun­gen mittels DRAGOset über die USB-Schnitt­stelle im Gerät pro­gram­mie­ren. Die DIP-Schalter S1-1 bis S1-4 müssen dann auf ON stehen (PC-Mode).


Device diagnostics
Device diagnostics


With the menu item "Device | Diagnostics ..." call to a diagnostic screen. In this window, you get an overview of the current measured values ​​and messages of the transmitter.

This requires an online connection to the transmitter.

Wiring of Terminals
Wiring of Terminals


Depending on the selec­ted input range and other parameters changes the wiring of the limit switch.

On this graph, you can see how the limit switch should be connec­ted in this mode. If you move your mouse over the image of the limit switch, the ter­mi­nal num­bers are displayed.

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