North
Q
Power & Gas Reader
Revision: 2.2
6
Register 1
-
Pulse factor
(4 byte register) - In this register the controlling node must set the
meter's impulse or rotation factor x 10.
Ex:
For a mechanical meter with a rotation factor of 150, the value for this register must be
set to 1500 (150 x 10). The rotation factor is usually written on the meter and its unit of
measurement is rot / kWh.
NOTE:
Some mechanical meters express their rotation factor in rot / Wh instead of rot / kWh.
In this case the value must be converted to rot / kWh before multiplying by 10 and writing this
value in the register. In order to convert rot / Wh to rot / kWh to value has to be multiplied by
1000.
For an electronic meter with an impulse factor of 1000 the value for this register must
be set to 10000 (1000 x 10). The impulse factor is usually written on the meter and its unit of
measurement is imp / kWh.
NOTE:
Some electronic meters express their impulse factor in imp / Wh instead of imp / kWh.
In this case the value must be converted to imp / kWh before multiplying by 10 and writing this
value in the register. In order to convert imp / Wh to imp / kWh the value from the meter has
to be multiplied by 1000.
For a gas meter read using the silver spot on one of the digits, the value written in this
register is calculated with the following formula:
value = Pow(10, x) where X is the index of the red digit that has the silver spot.
Figure 1 Determining the index of red digit with silver spot
For a gas meter read through magnetic contact, the value written in this register is
impulse factor * 10. The impulse factor is usually written on the meter and it's expressed in imp
/ m
3
.
Register 2
-
sensor type
(1 byte register) - In this register, the controlling node has to set the
meter type on which the Power Reader is placed.
For electricity firmware: set 0x01 to this register for electronic meter, or 0x02 for mechanical
meter. Mechanical meters can be distinguished by their rotating disk while the electronic
meters can be distinguished by their digital display and blinking LED.
