WATTrouter M - user manual
How to fit and setup the device
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Label – used to assign a label for the relevant input. Label may contain a maximum of 8 characters
in ASCII encoding. For ILx inputs it cannot be modified.
Measurement input settings (ILx):
Current orientation - it is used to change the sign of measured powers, if the current sensing module is
fitted in inverted position, or in cases for example, when it is desirable to pass the wire through the
module in inverted direction.
Phase - it is used to set the physical phase to given input. Assign the phase so that the measured
currents are in phase with voltage. Check the assignment using the input checking oscilloscope and a
purely resistive (thermal) load on the given phase.
Note:
The Phase parameter replaces the "Phase Order Setting" menu from older WATTrouter models
and allows you to set any phasing for all inputs with the power measurement function.
Ratio for external CTs - set this ratio only if you use additional external current transformers (CTs),
whose secondary coils are shorted with a wire passing through measuring coils of the current sensing
module, as specified on figure 7. If you use standard connection for WATTrouter device that is, the
facility or household supply wire is passing directly through measuring coils as specified on figure 3,
then this ratio should be 1:1 (however, this ratio can also be used to calibrate current measurement
even in the case of standard wiring without external measuring transformers). External current
transformers can extend the measuring range of the controller up to any value, depending on the
conversion rate of the external current transformer.
Example:
Let us say you want to use WATTrouter M SSR in a facility where the main circuit breaker is
rated up to 3x400A. In this case you have to buy external current transformers with ratio 400A:5A.
Connect/short-cut their secondary terminals using a wire, and at the same time, pass it through
measuring coils of the current sensing module (see figure 7). Now set the conversion rate to 400:5.
However, in order to use the full range of the built-in A/D converter, it is recommended to make 4
turns around the measuring coils to get optimum conversion rate of 400A:20A. Then, set the
conversion rate to 400:20.
Caution:
Use only external CTs for large facilities and large PV-plant power outputs. If you are using a
high conversion rate of external CTs, you have to take into account that (relatively) small power
outputs (in the example describing the optimized conversion rate 400A:20A, the limit represents
approximately 100 W per phase) are below the resolution capacity of the measuring inputs and
therefore, these power values will not be measured and equal to zero.
Note:
The setting is only possible for the IL1 input, other ILx inputs share the same configuration.
FB input settings:
Energy offset - this field can be used to set initial values of measured energies. If the values of
measured energies do not match the display on the connected energy meter (for example), put the
value of the energy shown on the display into this column and reset impulse counters to zero by
marking the option "Reset energy".
Reset energy - used to reset energy counters to zero.
Number of impulses per one kWh – this column is used to set the number of impulses per one kWh.
Set the value according to the label or manual of the connected energy meter, inverter or according to
another compatible measuring instrument. It is recommended to use highest possible amount of
impulses per kWh to get better resolution for the power fields in the “FB input status” group.
