Syntax
Global Options
| Option | Description |
|---|---|
--box TEXT | Lagerbox name or IP address |
--help | Show help message and exit |
Commands
| Command | Description |
|---|---|
voltage | Set or read output voltage with optional protection thresholds |
current | Set or read output current with optional protection thresholds |
enable | Enable power output (requires confirmation) |
disable | Disable power output (requires confirmation) |
state | Show current power state including measurements and protection status |
clear-ovp | Clear over-voltage protection fault |
clear-ocp | Clear over-current protection fault |
set | Set power supply mode |
tui | Launch interactive terminal UI for real-time monitoring and control |
CLI Validation Ranges
The CLI enforces conservative upper bounds before sending commands to hardware:| Parameter | Maximum | Notes |
|---|---|---|
| Voltage | 100.0 V | Most bench supplies are 30-60 V |
| Current | 30.0 A | Typical bench supply limit |
| OVP | 110.0 V | Can be slightly above max output |
| OCP | 33.0 A | Can be slightly above max output |
Command Reference
voltage
Set or read output voltage with optional protection thresholds.
VALUE- Voltage in volts. Omit to read the current voltage setting.
| Option | Type | Description |
|---|---|---|
--ovp FLOAT | Volts | Over-voltage protection threshold (must be >= voltage) |
--ocp FLOAT | Amps | Over-current protection threshold |
--yes | Flag | Apply without confirmation prompt |
--box TEXT | String | Lagerbox name or IP |
--yes is passed:
current
Set or read output current with optional protection thresholds.
VALUE- Current in amps. Omit to read the current limit setting.
| Option | Type | Description |
|---|---|---|
--ovp FLOAT | Volts | Over-voltage protection threshold |
--ocp FLOAT | Amps | Over-current protection threshold (must be >= current) |
--yes | Flag | Apply without confirmation prompt |
--box TEXT | String | Lagerbox name or IP |
--yes is passed:
enable
Enable power output to device. Requires confirmation to prevent accidental power-on.
| Option | Description |
|---|---|
--yes | Enable without confirmation prompt |
--box TEXT | Lagerbox name or IP |
disable
Disable power output. Requires confirmation to prevent accidental power-off.
| Option | Description |
|---|---|
--yes | Disable without confirmation prompt |
--box TEXT | Lagerbox name or IP |
state
Show comprehensive power supply state including measurements, setpoints, and protection status.
- Channel - Active channel on multi-channel supplies
- Enabled - Output ON or OFF
- Mode - CV (constant voltage) or CC (constant current)
- Voltage/Current/Power - Live measurements (4 decimal places)
- OCP/OVP Limit - Protection thresholds
- OCP/OVP Tripped - Whether protection has triggered (color-coded: green=NO, red=YES)
clear-ovp
Clear over-voltage protection fault. Use after an OVP trip to reset the protection and allow the output to be re-enabled.
clear-ocp
Clear over-current protection fault. Use after an OCP trip to reset the protection and allow the output to be re-enabled.
set
Set power supply mode. The available modes depend on the hardware.
tui
Launch an interactive terminal UI for real-time power supply monitoring and control. The TUI provides live-updating measurements, inline command entry, and keyboard shortcuts.
textual Python package (pip install textual).
TUI display:
- Live voltage, current, and power measurements (updated every second)
- Output status (ON/OFF) with color coding
- Mode indicator (CV/CC) with color coding
- Protection thresholds and trip status
- Hardware maximum ratings
- Scrollable command log
| Command | Description |
|---|---|
voltage [VALUE] | Set or read voltage |
current [VALUE] | Set or read current limit |
ocp [VALUE] | Set or read OCP threshold |
ovp [VALUE] | Set or read OVP threshold |
enable | Enable output |
disable | Disable output |
state | Display current state |
clear-ocp | Clear OCP trip |
clear-ovp | Clear OVP trip |
help | Show available commands |
clear | Clear the command log |
q / quit / exit | Exit the TUI |
| Key | Action |
|---|---|
q | Quit |
Ctrl+C | Quit |
r | Refresh display |
| Up/Down arrows | Navigate command history |
lager supply CLI commands (e.g., lager supply PSU voltage 3.3 --yes) will automatically route through the TUI’s WebSocket connection on port 9000, sharing the USB instrument connection. If the TUI is not running, commands use direct USB access.
OVP / OCP Protection
Over-voltage protection (OVP) and over-current protection (OCP) thresholds protect your device under test from damage. Setting thresholds:- All values must be positive
- OVP must be >= the voltage setpoint
- OCP must be >= the current setpoint
- Values are validated against CLI maximum limits before being sent to hardware
- The supply output is disabled automatically
stateshows the tripped status in red- Clear the fault with
clear-ovporclear-ocp - Re-enable the output with
enable
Supported Hardware
| Manufacturer | Model Series | Channels | Specs | Notes |
|---|---|---|---|---|
| Rigol | DP832 / DP832A | 3 | Ch1-2: 30V/3A, Ch3: 5V/3A | Most common |
| Rigol | DP821 | 2 | Ch1: 60V/1A, Ch2: 8V/10A | |
| Rigol | DP811 / DP811A | 1 | 20V/10A or 40V/5A (range) | |
| Keithley | 2281S | 1 | 20V/6A/120W | Battery simulator mode |
| Keysight | E36200 series | 2 | E36233A: 30V/20A per ch | Dual output |
| Keysight | E36300 series | 3 | E36311A/12A/13A | Triple output |
| EA | PSI/EL series | 1 | PSB 10080-60, PSB 10060-60 | Two-quadrant |
Default Net
Set a default power supply net to avoid specifying the name each time:Examples
Scripting Example
Troubleshooting
| Error | Cause | Fix |
|---|---|---|
| ”Resource busy” | TUI is using the supply’s USB connection | Close the TUI (press q), then retry |
| ”No route to host” | Box unreachable | Check VPN/Tailscale: lager hello --box <box> |
| Connection refused | Box service not running | Verify box is online: lager status --box <box> |
| OVP/OCP validation error | Protection threshold below setpoint | Set OVP >= voltage, OCP >= current |
| ”exceeds maximum limit” | Value above CLI safety limits | Check equipment specs; CLI max is 100V / 30A |
Notes
- All
voltageandcurrentset operations require confirmation (use--yesto skip) enableanddisablealso require confirmation- Net names refer to names assigned when setting up your testbed with
lager nets - The TUI connects via WebSocket (port 9000) for real-time updates
- Protection thresholds help prevent damage to your device under test
- Multi-channel supplies: each channel is configured as a separate net

