DRAGOset for Limit Alarm Switch 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
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.
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.
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 %)|
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:|
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.
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.
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.
The trip point can be teached-in and corrected during operation with the front-side teach-in push-buttons:
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.
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.
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.
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).
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.
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.