DMM

Take one reading from a bench digital multimeter (DMM) net. Each call sets the function, range and integration time, then reads. A reading never depends on the front panel or a previous caller.

Syntax

lager dmm [NETNAME] [FUNCTION] [OPTIONS]

Arguments

Argument	Description
`NETNAME`	DMM net name (optional if a default is set with `lager defaults add --dmm-net`)
`FUNCTION`	Measurement function (default `dcv`); see the table below

With a default net set, a single function argument reads the default net: lager dmm res measures resistance on it. A DMM net with the same name as a function takes precedence.

Function	Measures	Unit
`dcv` / `acv`	DC / AC voltage	V
`dci` / `aci`	DC / AC current	A
`res` / `fres`	2-wire / 4-wire resistance	ohm
`cont`	Continuity	ohm
`diode`	Diode forward voltage	V
`freq` / `period`	Frequency / period	Hz / s
`cap`	Capacitance	F
`temp`	Temperature	degC

Options

Option	Description
`--range FULL_SCALE`	Fixed range in base units (`20` = 20 V, `2e-6` = 2 uF), or `auto` (default)
`--nplc N`	Integration time in power-line cycles; `dcv`, `dci`, `res` and `fres` only
`--sensor PROBE`	Temperature probe for `temp`: `rtd:pt100`, `rtd:pt1000`, `ther:b`/`e`/`j`/`k`/`n`/`r`/`s`/`t`
`--errors`	Read and clear the meter’s error queue instead of measuring
`--idn`	Print the meter’s `*IDN?` reply instead of measuring
`--box TEXT`	Lager Box name or IP address
`--json`	Emit a JSON object instead of formatted text

The box refuses a range, NPLC value or sensor the meter does not support, and lists the valid values. It never rounds to the nearest setting.

Output

$ lager dmm VBAT --box my-lager-box
3.300124 V

$ lager dmm VBAT dcv --range 20 --nplc 10 --json --box my-lager-box
{"netname": "VBAT", "function": "dcv", "value": 3.300124, "unit": "V", "overload": false}

An over-range reading prints OVERLOAD, and an open continuity or diode input prints OPEN. With --json both give "value": null, "overload": true.

Supported Hardware

Device	Ranges	NPLC
Siglent SDM3065X	DCV 200 mV-1000 V, ACV 200 mV-750 V, DCI/ACI 200 uA-10 A, resistance 200 ohm-100 Mohm, capacitance 2 nF-100 mF	0.005, 0.05, 0.5, 1, 10, 100

The continuity range is 2 kohm and the diode range is 2 V. Frequency, period and temperature take no range.

Adding a DMM net

A USB-connected meter shows up in lager instruments and is added like any other net:

lager nets add VBAT dmm 1 USB0::0xF4EC::0x1203::<serial>::INSTR --box my-lager-box

A LAN-connected meter is not found by the USB scan. Add it with lager nets add-batch:

[{"name": "VBAT", "role": "dmm", "channel": "1",
  "instrument": "Siglent_SDM3065X", "address": "TCPIP::192.168.1.60::INSTR"}]

Examples

# 4-wire resistance on the 2 kOhm range, slowest integration
lager dmm RSENSE fres --range 2000 --nplc 100 --box my-lager-box

# Quiescent current
lager dmm IQ dci --range 2e-3 --box my-lager-box

# PT100 temperature
lager dmm TPROBE temp --sensor rtd:pt100 --box my-lager-box

# Resistance on the default DMM net
lager dmm res --box my-lager-box

# List DMM nets
lager dmm --box my-lager-box

Lager Box Management

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I/O & Communication

Security

Development

Utilities

Syntax

Arguments

Options

Output

Supported Hardware

Adding a DMM net

Examples

​Syntax

​Arguments

​Options

​Output

​Supported Hardware

​Adding a DMM net

​Examples

Syntax

Arguments

Options

Output

Supported Hardware

Adding a DMM net

Examples