Infratek 106A / LEM D 4000 (Infratek OEM) Python GPIB Driver

Blocking driver for Infratek 106A power analyzers. Single-shot (STOP) mode. Requires pyvisa + NI-VISA. Early LEM D 4000 Devices are made by Infratek and will ID as 306A

pip install pyvisa

Quick Start

from infratek_106a import Infratek106A

with Infratek106A() as dev:
    dev.configure(current_input="IN30", sync_source="CURR", aperture="250M", phase="L1")
    dev.trigger()
    print(dev.voltage_rms())
    print(dev.current_rms("L2"))  # switches phase automatically

Constructor

Infratek106A(resource="GPIB0::5::INSTR", timeout_ms=10000, warmup_count=1)

warmup_count — number of discard triggers after any config change. The device returns garbage data for the first N measurements after changing acquisition settings (range, aperture, input, etc.). Increase if readings are unstable after config changes.

configure()

All parameters optional. Only sends commands for what you pass. Batches ACQ commands into a single STOP/restart cycle.

dev.configure(
    current_input="IN30",     # "IN5", "IN30", "SH"
    sync_source="CURR",       # "VOLT", "CURR"
    aperture="500M",          # "100M", "250M", "500M", "1", "2"
    voltage_range="Auto",     # "Auto", "300M", "1", "3", "10", "30", "100", "300", "1000"
    current_range="Auto",     # depends on input: IN30→"1".."100", IN5→"15M".."15", SH→"60M".."6"
    phase="L1",               # "L1", "L2", "L3"
    warmup_count=3,
)

Trigger + Read

dev.trigger()  # blocking, waits for acquisition complete

# All read methods accept optional phase parameter
v = dev.voltage_rms()
v = dev.voltage_rms("L2")

Scalar Readings

All accept optional phase parameter.

Voltage	Current	Power	Energy
voltage_rms()	current_rms()	power_active()	energy_active()
voltage_rms_ac()	current_rms_ac()	power_apparent()	energy_apparent()
voltage_rect()	current_rect()	power_reactive()
voltage_mean()	current_mean()	power_factor()
voltage_min()	current_min()	power_active_ac()
voltage_max()	current_max()	power_apparent_ac()
voltage_peak()	current_peak()	power_reactive_ac()
voltage_crest()	current_crest()	power_factor_ac()
voltage_form()	current_form()
voltage_thd()	current_thd()
	current_int()
frequency()

Other: energy_reset(), current_reset(), acquisition_quality(), error(), identify()

3-Phase Bulk Read

One trigger, read all phases:

dev.configure(current_input="IN30", sync_source="CURR", aperture="500M", phase="L1")
dev.trigger()

for ph in ("L1", "L2", "L3"):
    v = dev.voltage_rms(ph)
    i = dev.current_rms(ph)
    p = dev.power_active(ph)
    print(f"{ph}: {v:.2f} V  {i:.4f} A  {p:.2f} W")

FFT Harmonics

Harmonics 1–99. Returns list[float].

dev.trigger()
v_harmonics = dev.voltage_fft(1, 50, "L1")
i_harmonics = dev.current_fft(1, 50, "L1")
p_harmonics = dev.power_fft(1, 50, "L1")

Plot:

import matplotlib.pyplot as plt

dev.trigger()
i_fft = dev.current_fft(1, 50, "L1")
v_fft = dev.voltage_fft(1, 50, "L1")

fig, (ax1, ax2) = plt.subplots(2, 1, sharex=True)
ax1.bar(range(1, 51), v_fft)
ax1.set_ylabel("Voltage (V)")
ax2.bar(range(1, 51), i_fft)
ax2.set_ylabel("Current (A)")
ax2.set_xlabel("Harmonic #")
plt.show()

Analog Inputs

Channels 0–7. Returns list[float].

dev.trigger()
ainp = dev.analog_inputs(0, 7)
for ch, val in enumerate(ainp):
    print(f"CH{ch}: {val:.6f}")

GUI Integration

Blocking driver — use a worker thread:

import threading

def worker():
    dev.trigger()
    v = dev.voltage_rms()
    # update GUI from here

t = threading.Thread(target=worker)
t.start()