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Energy and Power Information

This document explains energy and power data availability on the Grundfos ALPHA HWR pump.

Summary

  • Instantaneous Power (W) - Available via telemetry streaming
  • Cumulative Energy (kWh) - NOT available on ALPHA HWR

Instantaneous Power and Electrical Data

Available via Telemetry

Real-time power consumption, grid voltage, and current are available through the Motor State telemetry object.

Protocol Details: - Class: 10 (DataObject) - SubID: 0x0045 (69) - ObjID: 0x0057 (87) - Streaming: Automatic notifications when pump is running - Update Rate: ~10 Hz

Data Format (Motor State):

Offset Type Unit Description
+0 Float32 V Grid voltage (AC)
+8 Float32 A Current
+16 Float32 W Power consumption
+20 Float32 RPM Actual motor speed

Example: 

# The library automatically updates these fields in the telemetry snapshot
telemetry = await client.telemetry.read_once()

print(f"Grid Voltage: {telemetry.voltage_ac_v} V")
print(f"Current: {telemetry.current_a} A")
print(f"Power: {telemetry.power_w} W")
print(f"Speed: {telemetry.speed_rpm} RPM")

Typical Values: - Voltage: 115-125 V (Residential US) - Power: 2-38 W (ALPHA HWR 15-60) - Speed: 0-4500 RPM - Current: 0.05-0.4 A

Cumulative Energy Consumption - NOT SUPPORTED

Object 77 Investigation

The GENI protocol documentation mentions Object 77 (power_and_energy_info_obj) for storing cumulative energy data. However, the ALPHA HWR does NOT implement this object.

Hardware Testing Results:

All SubIDs tested on a real ALPHA HWR (Family 52, Type 7) returned empty responses:

# Test results for Object 77
SubID 0:    No data (status 0x81 = not available)
SubID 1:    No data
SubID 2:    No data

Workaround: Manual Calculation

You can estimate cumulative energy from operating hours and average power:

stats = await client.device_info.read_statistics()
operating_hours = stats.operating_hours

# Assume average power consumption (depends on usage pattern)
avg_power_w = 15.0 

# Calculate approximate energy
energy_kwh = (operating_hours * avg_power_w) / 1000.0
print(f"Estimated energy: {energy_kwh:.2f} kWh")

Comparison with Statistics

Available Data (Object 93)

The pump DOES provide cumulative operating statistics via Object 93, SubID 1:

stats = await client.device_info.read_statistics()
print(f"Operating hours: {stats.operating_hours:.1f} h")
print(f"Start count: {stats.start_count}")

Object 93 Data: - Operating Hours - Total runtime in hours - Start Count - Number of pump starts

Summary Table

Feature Available Source Update Rate
Instantaneous Power (W) Yes Object 0x0045/0x0057 ~10 Hz
Grid Voltage (V) Yes Object 0x0045/0x0057 ~10 Hz
Current (A) Yes Object 0x0045/0x0057 ~10 Hz
Cumulative Energy (kWh) No - -
Operating Hours Yes Object 93 On-demand
Start Count Yes Object 93 On-demand