Peterphrastus

With the current emphasis on conserving power, RHS can now be set up to monitor and report on power usage for two circuits. These can be whole house or two selected circuits such as HVAC, hot water, pool heater etc. In addition, a voltage sensor can be installed to monitor voltage fluctuations and provide a more precise accounting of kilowatt hour usage. However, if a voltage sensor is added, it must occupy analog input 2. This means that an indoor humidity sensor cannot be used. The recommended sensors are available from Elkor Technologies Inc. .

“Sensor” is checked to enable the associated current or voltage sensor.

“Max amps” for each current sensor is set to the full scale reading the sensor can provide.

“Sensitivity” sets the minimum change that must occur before RHS logs the change. For current, this can be set to the equivalent of approximately 100 watts. If the voltage is 120 then for Current, a value of 1 amp is reasonable. For voltage, a value of 1 percent of the Default is a good starting poiint. Smaller values may cause excessive logging activity.

“Power factor” is a complex quantity to measure. For most purposes, a value of 0.9 will suffice.

“Full duplex” is checked when the sensor is installed on a circuit that uses both lines of a domestic supply. For example: a 220/240 volt hot water heater.

“Max volts” sets the full scale reading the voltage sensor is calibrated to provide.

“Default voltage” is always set. This value should be set to the expected average voltage.

”Peak kWh usage interval” is usually set to the value the utility company uses for billing if applicable. RHS will record the time of day that the peak period was attained. This value applies to the sum of the two lines with sensors.

"Maximum sensor saturation" provides a means of supressing large instantaneous voltage and current spikes that occur when air conditioners and heat pumps start up.