about namur sensor

[dcset]

Hi everybody i´m trying to control speed on a genset with a namur sensor connected with a weidmuller was4 pro freq, and with the unit stopped i saw the led on the weidmuller is flashing and i wonder if this ok.
I asume that the contact on the namur sensor is a dry contact that open or close depending when metal parts are close to te sensor, but i measure, the voltage and i find 2,5 V dc aprox with the contact closed and 6,8 V dc when the contact is opened... i disconnect the weidmuller and i measure the contact resistance and is about 300 kohms with no metal close and 700 kohms when the sensor is near to metal pieces.
I´ll like to know what is the normal values... cause in few days i want to run the unit and if i have a problem i want to solve.
Why the led is flashing? thanks a lot....

 

[waross]

Does this help??
Setting the input range using the DIP
switches (no frequency generator
required):
There are 2 different cases:
1. Lower measuring frequency = 0 Hz
– Choose operating mode “= … fmax” S2.3 = 0
and S2.4 = 0
– Set the upper measuring frequency using DIP
switches S1 and S2.1, S2.2 (see table)
– That's all
2. Lower measuring frequency  0 Hz
– First the lower measuring frequency
must be saved.
Select mode “save fmin”.
S2.3 = 1 and S2.4 = 0.
Set the frequency using DIP switches S1 and
S2.1, S2.2 (see table)
To save the frequency, briefly connect the module
to the power supply.
– Select mode “fmin…fmax”
S2.3 = 0 and S2.4 = 1
– Set the upper measuring frequency using DIP
switches S1 and S2.1, S2.2 (see table).
– That's all.
Adjusting the input range using
a frequency generator
– Select the switch setting for saving the frequency:
S2.1 = 0, S2.2 = 1, S2.3 = 1 and S2.4 = 1
– Apply min. frequency to the module
– Connect the module to the power supply
– The LED lights up when the input frequency is
being measured. If the LED goes off, the frequency
has been saved and the module can be disconnected
from the power supply again.
– Repeat with max. frequency:
S2.1 = 1, S2.2 = 0, S2.3 = 1 and S2.4 = 1
– Select special range:
S2.1 = 1, S2.2 = 1, S2.3 = 1 and S2.4 = 1
You'll find it here

http://www.clrwtr.com/PDF/Weidmuller/Weidmuller-F-DC-Isolating-Transformers.pdf

personally I would want more information before I felt comfortable using this device. For instance the output is usually reversed for generator control. 20...4 ma rather than 4...20 ma.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[dcset]

Thanks,
This devices must be configurated from factory, cause we have asked for it, but what i don´t know if its normal that it´s all time flashing when the unit is stopped.

thanks.