Example of an application "Determining transmit power"
The aim is to find the minimum transmit power with which a transponder can be identified.
The "Power Ramp" function of the RF620R and RF630R readers allows the reader to
increase the transmit power automatically if no transponder is identified in the field. This
function can be used to obtain the power settings of a reading point.
The reading point is fully installed and the reader is connected to the SIMATIC RF-DIAG tool
via the PC adapter. Make sure that you make changes to the values of the Power Ramp
based on real environmental conditions.
1. Select the "Power Ramp" tab in SIMATIC RF-DIAG. You will find a precise description of
2. Make the settings for the Power Ramp as follows:
If the parameter settings for the setup have been optimized, the required power is selected
automatically by the algorithm to perform transponder inventories. After several runs, the
necessary power for identifying the transponders reaches a maximum value between the
Power Ramp low limit and the Power Ramp high limit.
Adopt the power settings in SIMATIC RF-DIAG in the PLC or STEP 7 application:
● By selecting the achieved maximum power for ANT1 using RESET[distance_limiting, bit
● By using the Power Ramp algorithm set here, situation-specific adaptation of the power is
Operating Manual, 09/2012, C79000-G8976-C292-01
the Power ramp algorithm in the relevant section of the "SIMATIC RF620R/RF630R
Configuration Manual (http://support.automation.siemens.com/WW/view/en/33287195)".
– For each antenna to be used, select a low power limit (corresponds to ANT1:
RESET[distance_limiting, bit 0-3] and ANT2: RESET[distance_limiting, bit 4-7])
– Select a power increase per step (Boost Step Size ANT1, Boost Step Size ANT2)
– Select the maximum power increase to be reached after n steps (Boost Max ANT1,
Boost Max ANT2)
– Select the number of consecutive inventories to be taken via ANT1 or ANT2 before
the power is increased by a step (Boost Threshold ANT1, Boost Threshold ANT2)
– The Power Ramp remains at the transmit power at which the transponder was
0-3] and for ANT2 using, RESET[distance_limiting, bit 4-7], it is possible to ensure
identification of the transponder.
6.3 Example of an application "Determining transmit power"