Hewlett-Packard

`HP3456a` Digital Voltmeter

class instruments.hp.HP3456a(filelike)[source]

The HP3456a is a 6 1/2 digit bench multimeter.

It supports DCV, ACV, ACV + DCV, 2 wire Ohms, 4 wire Ohms, DCV/DCV Ratio, ACV/DCV Ratio, Offset compensated 2 wire Ohms and Offset compensated 4 wire Ohms measurements.

Measurements can be further extended using a system math mode that allows for pass/fail, statistics, dB/dBm, null, scale and percentage readings.

HP3456a is a HPIB / pre-448.2 instrument.

class MathMode(*values)[source]

Enum with the supported math modes

db = 9

dbm = 4

null = 3

off = 0

pass_fail = 1

percent = 8

scale = 7

statistic = 2

thermistor_c = 6

thermistor_f = 5

class Mode(*values)[source]

Enum containing the supported mode codes

acv = 'S0F2': AC voltage

acvdcv = 'S0F3': RMS of DC + AC voltage

dcv = 'S0F1': DC voltage

oc_resistence_2wire = 'S1F4': offset compensated 2 wire resistance

oc_resistence_4wire = 'S1F5': offset compensated 4 wire resistance

ratio_acv_dcv = 'S1F2': ratio AC / DC voltage

ratio_acvdcv_dcv = 'S1F3': ratio (AC + DC) / DC voltage

ratio_dcv_dcv = 'S1F1': ratio DC / DC voltage

resistance_2wire = 'S0F4': 2 wire resistance

resistance_4wire = 'S0F5': 4 wire resistance

class Register(*values)[source]

Enum with the register names for all HP3456a internal registers.

count = 'C'

delay = 'D'

lower = 'L'

mean = 'M'

nplc = 'I'

number_of_digits = 'G'

number_of_readings = 'N'

r = 'R'

upper = 'U'

variance = 'V'

y = 'Y'

z = 'Z'

class TriggerMode(*values)[source]

Enum with valid trigger modes.

external = 2

hold = 4

internal = 1

single = 3

class ValidRange(*values)[source]

Enum with the valid ranges for voltage, resistance, and number of powerline cycles to integrate over.

nplc = (0.1, 1.0, 10.0, 100.0)

resistance = (100.0, 1000.0, 10000.0, 100000.0, 1000000.0, 10000000.0, 100000000.0, 1000000000.0)

voltage = (0.1, 1.0, 10.0, 100.0, 1000.0)

auto_range()[source]: Set input range to auto. The HP3456a should upscale when a reading is at 120% and downscale when it below 11% full scale. Note that auto ranging can increase the measurement time.

fetch(mode=None)[source]

Retrieve n measurements after the HP3456a has been instructed to perform a series of similar measurements. Typically the mode, range, nplc, analog filter, autozero is set along with the number of measurements to take. The series is then started at the trigger command.

Example usage:

>>> dmm.number_of_digits = 6
>>> dmm.auto_range()
>>> dmm.nplc = 1
>>> dmm.mode = dmm.Mode.resistance_2wire
>>> n = 100
>>> dmm.number_of_readings = n
>>> dmm.trigger()
>>> time.sleep(n * 0.04)
>>> v = dmm.fetch(dmm.Mode.resistance_2wire)
>>> print len(v)
10

Parameters:: mode (HP3456a.Mode) – Desired measurement mode. If not specified, the previous set mode will be used, but no measurement unit will be returned.
Returns:: A series of measurements from the multimeter.
Return type:: Quantity

measure(mode=None)[source]

Instruct the HP3456a to perform a one time measurement. The measurement will use the current set registers for the measurement (number_of_readings, number_of_digits, nplc, delay, mean, lower, upper, y and z) and will immediately take place.

Note that using HP3456a.measure() will override the trigger_mode to HP3456a.TriggerMode.single

Example usage:

>>> dmm = ik.hp.HP3456a.open_gpibusb("/dev/ttyUSB0", 22)
>>> dmm.number_of_digits = 6
>>> dmm.nplc = 1
>>> print dmm.measure(dmm.Mode.resistance_2wire)

Parameters:: mode (HP3456a.Mode) – Desired measurement mode. If not specified, the previous set mode will be used, but no measurement unit will be returned.
Returns:: A measurement from the multimeter.
Return type:: Quantity

trigger()[source]: Signal a single manual trigger event to the HP3456a.

property autozero

Set the autozero mode.

This is used to compensate for offsets in the dc input amplifier circuit of the multimeter. If set, the amplifier”s input circuit is shorted to ground prior to actual measurement in order to take an offset reading. This offset is then used to compensate for drift in the next measurement. When disabled, one offset reading is taken immediately and stored into memory to be used for all successive measurements onwards. Disabling autozero increases the HP3456a”s measurement speed, and also makes the instrument more suitable for high impendance measurements since no input switching is done.

property count

Get the number of measurements taken from HP3456a.Register.count when in HP3456a.MathMode.statistic.

Return type:: int

property delay

Get/set the delay that is waited after a trigger for the input to settle using HP3456a.Register.delay.

Type:: As specified, assumed to be s otherwise
Return type:: s

property filter

Set the analog filter mode.

The HP3456a has a 3 pole active filter with greater than 60dB attenuation at frequencies of 50Hz and higher. The filter is applied between the input terminals and input amplifier. When in ACV or ACV+DCV functions the filter is applied to the output of the ac converter and input amplifier. In these modes select the filter for measurements below 400Hz.

property input_range

Set the input range to be used.

The HP3456a has separate ranges for ohm and for volt. The range value sent to the instrument depends on the unit set on the input range value. auto selects auto ranging.

Type:: Quantity

property lower

Get/set the value in HP3456a.Register.lower, which indicates the lowest value measurement made while in HP3456a.MathMode.statistic, or the lowest value preset for HP3456a.MathMode.pass_fail.

Type:: float

property math_mode

Set the math mode.

The HP3456a has a number of different math modes that can change measurement output, or can provide additional statistics. Interaction with these modes is done via the HP3456a.Register.

Type:: HP3456a.MathMode

property mean

Get the mean over HP3456a.Register.count measurements from HP3456a.Register.mean when in HP3456a.MathMode.statistic.

Return type:: float

property mode

Set the measurement mode.

Type:: HP3456a.Mode

property nplc

Get/set the number of powerline cycles to integrate per measurement using HP3456a.Register.nplc.

Setting higher values increases accuracy at the cost of a longer measurement time. The implicit assumption is that the input reading is stable over the number of powerline cycles to integrate.

Type:: int

property number_of_digits

Get/set the number of digits used in measurements using HP3456a.Register.number_of_digits.

Set to higher values to increase accuracy at the cost of measurement speed.

Type:: int

property number_of_readings

Get/set the number of readings done per trigger/measurement cycle using HP3456a.Register.number_of_readings.

Type:: float
Return type:: float

property r

Get/set the value in HP3456a.Register.r, which indicates the resistor value used while in HP3456a.MathMode.dbm or the number of recalled readings in reading storage mode.

Type:: float
Return type:: float

property relative

Enable or disable HP3456a.MathMode.Null on the instrument.

Type:: bool

property trigger_mode

Set the trigger mode.

Note that using HP3456a.measure() will override the trigger_mode to HP3456a.TriggerMode.single.

Type:: HP3456a.TriggerMode

property upper

Get/set the value in HP3456a.Register.upper, which indicates the highest value measurement made while in HP3456a.MathMode.statistic, or the highest value preset for HP3456a.MathMode.pass_fail.

Type:: float
Return type:: float

property variance

Get the variance over HP3456a.Register.count measurements from HP3456a.Register.variance when in HP3456a.MathMode.statistic.

Return type:: float

property y

Get/set the value in HP3456a.Register.y to be used in calculations when in HP3456a.MathMode.scale or HP3456a.MathMode.percent.

Type:: float
Return type:: float

property z

Get/set the value in HP3456a.Register.z to be used in calculations when in HP3456a.MathMode.scale or the first reading when in HP3456a.MathMode.statistic.

Type:: float
Return type:: float

`HP6624a` Power Supply

class instruments.hp.HP6624a(filelike)[source]

The HP6624a is a multi-output power supply.

This class can also be used for HP662xa, where x=1,2,3,4,7. Note that some models have fewer channels than the HP6624, and it is up to the user to take this into account. This can be changed with the channel_count property.

Example usage:

>>> import instruments as ik
>>> psu = ik.hp.HP6624a.open_gpibusb('/dev/ttyUSB0', 1)
>>> psu.channel[0].voltage = 10 # Sets channel 1 voltage to 10V.

class Channel(hp, idx)[source]

Class representing a power output channel on the HP6624a.

Warning

This class should NOT be manually created by the user. It is designed to be initialized by the HP6624a class.

query(cmd)[source]

Function used to send a command to the instrument while wrapping the command with the neccessary identifier for the channel.

Parameters:: cmd (str) – Command that will be sent to the instrument after being prefixed with the channel identifier
Returns:: The result from the query
Return type:: str

reset()[source]: Reset overvoltage and overcurrent errors to resume operation.

sendcmd(cmd)[source]

Function used to send a command to the instrument while wrapping the command with the neccessary identifier for the channel.

Parameters:: cmd (str) – Command that will be sent to the instrument after being prefixed with the channel identifier

property current

Gets/sets the current of the specified channel. If the device is in constant voltage mode, this sets the current limit.

Note there is no bounds checking on the value specified.

Units:: As specified, or assumed to be \(\text{A}\) otherwise.
Type:: float or Quantity

property current_sense

Gets the actual output current as measured by the instrument for the specified channel.

Units:: \(\text{A}\) (amps)
Return type:: Quantity

property mode: Gets/sets the mode for the specified channel.

property output

Gets/sets the outputting status of the specified channel.

This is a toggle setting. True will turn on the channel output while False will turn it off.

Type:: bool

property overcurrent

Gets/sets the overcurrent protection setting for the specified channel.

This is a toggle setting. It is either on or off.

Type:: bool

property overvoltage

Gets/sets the overvoltage protection setting for the specified channel.

Note there is no bounds checking on the value specified.

Units:: As specified, or assumed to be \(\text{V}\) otherwise.
Type:: float or Quantity

property voltage

Gets/sets the voltage of the specified channel. If the device is in constant current mode, this sets the voltage limit.

Note there is no bounds checking on the value specified.

Units:: As specified, or assumed to be \(\text{V}\) otherwise.
Type:: float or Quantity

property voltage_sense

Gets the actual voltage as measured by the sense wires for the specified channel.

Units:: \(\text{V}\) (volts)
Return type:: Quantity

class Mode(*values)[source]

Enum holding typical valid output modes for a power supply.

However, for the HP6624a I believe that it is only capable of constant-voltage output, so this class current does not do anything and is just a placeholder.

current = 0

voltage = 0

clear()[source]

Taken from the manual:

Return the power supply to its power-on state and all parameters are returned to their initial power-on values except the following:

The store/recall registers are not cleared.
The power supply remains addressed to listen.
The PON bit in the serial poll register is cleared.

property channel

Gets a specific channel object. The desired channel is specified like one would access a list.

Return type:: HP6624a.Channel

`HP6632b` Power Supply

class instruments.hp.HP6632b(filelike, *args, **kwargs)[source]

The HP6632b is a system dc power supply with an output rating of 0-20V/0-5A, precision low current measurement and low output noise.

According to the manual this class MIGHT be usable for any HP power supply with a model number

HP663Xb with X in {1, 2, 3, 4},
HP661Xc with X in {1,2, 3, 4} and
HP663X2A for X in {1, 3}, without the additional measurement capabilities.

HOWEVER, it has only been tested by the author with HP6632b supplies.

Example usage:

>>> import instruments as ik
>>> psu = ik.hp.HP6632b.open_gpibusb('/dev/ttyUSB0', 6)
>>> psu.voltage = 10             # Sets voltage to 10V.
>>> psu.output = True            # Enable output
>>> psu.voltage
array(10.0) * V
>>> psu.voltage_trigger = 20     # Set transient trigger voltage
>>> psu.init_output_trigger()    # Prime instrument to initiated state, ready for trigger
>>> psu.trigger()                # Send trigger
>>> psu.voltage
array(10.0) * V

class ALCBandwidth(*values)[source]

Enum containing valid ALC bandwidth modes for the hp6632b

fast = 60000

normal = 15000

class DFISource(*values)[source]

Enum containing valid DFI sources for the hp6632b

event_status_bit = 'ESB'

off = 'OFF'

operation = 'OPER'

questionable = 'QUES'

request_service_bit = 'RQS'

class DigitalFunction(*values)[source]

Enum containing valid digital function modes for the hp6632b

data = 'DIG'

remote_inhibit = 'RIDF'

class ErrorCodes(*values)[source]

Enum containing generic-SCPI error codes along with codes specific to the HP6632b.

block_data_error = -160

block_data_not_allowed = -168

cal_not_enabled = 403

cal_password_incorrect = 402

cal_switch_prevents_cal = 401

character_data_error = -140

character_data_not_allowed = -148

character_data_too_long = -144

command_error = -100

command_header_error = -110

command_only_applic_rs232 = 602

computed_prog_cal_constants_incorrect = 405

computed_readback_cal_const_incorrect = 404

curr_or_volt_fetch_incompat_with_last_acq = 603

cv_or_cc_status_incorrect = 407

data_out_of_range = -222

data_type_error = -104

digital_io_selftest = 80

execution_error = -200

exponent_too_large = -123

expression_error = -170

expression_not_allowed = -178

front_panel_uart_buffer_overrun = 223

front_panel_uart_framing = 221

front_panel_uart_overrun = 220

front_panel_uart_parity = 222

front_panel_uart_timeout = 224

get_not_allowed = -105

header_separator_error = -111

header_suffix_out_of_range = -114

illegal_macro_label = -273

illegal_parameter_value = -224

incorrect_seq_cal_commands = 406

ingrd_recv_buffer_overrun = 213

invalid_block_data = -161

invalid_character = -101

invalid_character_data = -141

invalid_character_in_number = -121

invalid_expression = -171

invalid_inside_macro_definition = -183

invalid_outside_macro_definition = -181

invalid_separator = -103

invalid_string_data = -151

invalid_suffix = -131

macro_error_180 = -180

macro_error_270 = -270

macro_execution_error = -272

macro_parameter_error = -184

macro_recursion_error = -276

macro_redefinition_not_allowed = -277

measurement_overrange = 604

missing_parameter = -109

no_error = 0

numeric_data_error = -120

numeric_data_not_allowed = -128

operation_complete = -800

out_of_memory = -225

output_mode_must_be_normal = 408

ovdac_selftest = 15

parameter_not_allowed = -108

power_on = -500: Raised when the instrument detects that it has been turned from off to on.

program_mnemonic_too_long = -112

query_deadlocked = -430

query_error = -400

query_interrupted = -410

query_unterminated = -420

query_unterminated_after_indefinite_response = -440

ram_cal_checksum_failed = 3

ram_config_checksum_failed = 2

ram_rd0_checksum_failed = 1

ram_rst_checksum_failed = 5

ram_selftest = 10

ram_state_checksum_failed = 4

request_control_event = -700

rs232_recv_framing_error = 216

rs232_recv_overrun_error = 218

rs232_recv_parity_error = 217

string_data_error = -150

string_data_not_allowed = -158

suffix_error = -130

suffix_not_allowed = -138

suffix_too_long = -134

syntax_error = -102

system_error = -310

too_many_digits = -124

too_many_errors = -350

too_many_sweep_points = 601

too_much_data = -223

undefined_header = -113

unexpected_number_of_parameters = -115

user_request_event = -600

vdac_idac_selftest1 = 11

vdac_idac_selftest2 = 12

vdac_idac_selftest3 = 13

vdac_idac_selftest4 = 14

class RemoteInhibit(*values)[source]

Enum containing vlaid remote inhibit modes for the hp6632b.

latching = 'LATC'

live = 'LIVE'

off = 'OFF'

class SenseWindow(*values)[source]

Enum containing valid sense window modes for the hp6632b.

hanning = 'HANN'

rectangular = 'RECT'

abort_output_trigger()[source]: Set the output trigger system to the idle state.

check_error_queue()[source]: Checks and clears the error queue for this device, returning a list of ErrorCodes or int elements for each error reported by the connected instrument.

init_output_trigger()[source]: Set the output trigger system to the initiated state. In this state, the power supply will respond to the next output trigger command.

property current_sense_range

Get/set the sense current range by the current max value.

A current of 20mA or less selects the low-current range, a current value higher than that selects the high-current range. The low current range increases the low current measurement sensitivity and accuracy.

Units:: As specified, or assumed to be \(\text{A}\) otherwise.
Type:: float or Quantity

property current_trigger

Gets/sets the pending triggered output current.

Note there is no bounds checking on the value specified.

Units:: As specified, or assumed to be \(\text{A}\) otherwise.
Type:: float or Quantity

property digital_data

Get/set digital in+out port to data. Data can be an integer from 0-7.

Type:: int

property digital_function

Get/set the inhibit+fault port to digital in+out or vice-versa.

Type:: DigitalFunction

property display_brightness

Brightness of the display on the connected instrument, represented as a float ranging from 0 (dark) to 1 (full brightness).

Type:: float

property display_contrast

Contrast of the display on the connected instrument, represented as a float ranging from 0 (no contrast) to 1 (full contrast).

Type:: float

property init_output_continuous

Get/set the continuous output trigger. In this state, the power supply will remain in the initiated state, and respond continuously on new incoming triggers by applying the set voltage and current trigger levels.

Type:: bool

property line_frequency

Gets/sets the power line frequency setting for the instrument.

Returns:: The power line frequency
Units:: Hertz
Type:: Quantity

property output_dfi

Get/set the discrete fault indicator (DFI) output from the dc source. The DFI is an open-collector logic signal connected to the read panel FLT connection, that can be used to signal external devices when a fault is detected.

Type:: bool

property output_dfi_source

Get/set the source for discrete fault indicator (DFI) events.

Type:: DFISource

property output_protection_delay

Get/set the time between programming of an output change that produces a constant current condition and the recording of that condigition in the Operation Status Condition register. This command also delays over current protection, but not overvoltage protection.

Units:: As specified, or assumed to be \(\text{s}\) otherwise.
Type:: float or Quantity

property output_remote_inhibit

Get/set the remote inhibit signal. Remote inhibit is an external, chassis-referenced logic signal routed through the rear panel INH connection, which allows an external device to signal a fault.

Type:: RemoteInhibit

property sense_sweep_interval

Get/set the digitizer sample spacing. Can be set from 15.6 us to 31200 seconds, the interval will be rounded to the nearest 15.6 us increment.

Units:: As specified, or assumed to be \(\text{s}\) otherwise.
Type:: float or Quantity

property sense_sweep_points

Get/set the number of points in a measurement sweep.

Type:: int

property sense_window

Get/set the measurement window function.

Type:: SenseWindow

property voltage_alc_bandwidth

Get the “automatic level control bandwidth” which for the HP66332A and HP6631-6634 determines if the output capacitor is in circuit. Normal denotes that it is, and Fast denotes that it is not.

Type:: ALCBandwidth

property voltage_trigger

Gets/sets the pending triggered output voltage.

Note there is no bounds checking on the value specified.

Units:: As specified, or assumed to be \(\text{V}\) otherwise.
Type:: float or Quantity

`HP6652a` Single Output Power Supply

class instruments.hp.HP6652a(filelike, *args, **kwargs)[source]

The HP6652a is a single output power supply.

Because it is a single channel output, this object inherits from both PowerSupply and PowerSupply.Channel.

According to the manual, this class MIGHT be usable for any HP power supply with a model number HP66XYA, where X is in {4,5,7,8,9} and Y is a digit(?). (e.g. HP6652A and HP6671A)

HOWEVER, it has only been tested by the author with an HP6652A power supply.

Example usage:

>>> import time
>>> import instruments as ik
>>> psu = ik.hp.HP6652a.open_serial('/dev/ttyUSB0', 57600)
>>> psu.voltage = 3 # Sets output voltage to 3V.
>>> psu.output = True
>>> psu.voltage
array(3.0) * V
>>> psu.voltage_sense < 5
True
>>> psu.output = False
>>> psu.voltage_sense < 1
True
>>> psu.display_textmode=True
>>> psu.display_text("test GOOD")
'TEST GOOD'
>>> time.sleep(5)
>>> psu.display_textmode=False

display_text(text_to_display)[source]

Sends up to 12 (uppercase) alphanumerics to be sent to the front-panel LCD display. Some punctuation is allowed, and can affect the number of characters allowed. See the programming manual for the HP6652A for more details.

Because the maximum valid number of possible characters is 15 (counting the possible use of punctuation), the text will be truncated to 15 characters before the command is sent to the instrument.

If an invalid string is sent, the command will fail silently. Any lowercase letters in the text_to_display will be converted to uppercase before the command is sent to the instrument.

No attempt to validate punctuation is currently made.

Because the string cannot be read back from the instrument, this method returns the actual string value sent.

Parameters:: text_to_display ('str') – The text that you wish to have displayed on the front-panel LCD
Returns:: Returns the version of the provided string that will be send to the instrument. This means it will be truncated to a maximum of 15 characters and changed to all upper case.
Return type:: str

reset()[source]: Reset overvoltage and overcurrent errors to resume operation.

property channel

Return the channel (which in this case is the entire instrument, since there is only 1 channel on the HP6652a.)

Return type:: ‘tuple’ of length 1 containing a reference back to the parent HP6652a object.

property current

Gets/sets the output current.

Note there is no bounds checking on the value specified.

Units:: As specified, or assumed to be \(\text{A}\) otherwise.
Type:: float or Quantity

property current_sense

Gets the actual output current as measured by the sense wires.

Units:: \(\text{A}\) (amps)
Return type:: Quantity

property display_textmode

Gets/sets the display mode.

This is a toggle setting. True will allow text to be sent to the front-panel LCD with the display_text() method. False returns to the normal display mode.

`HPe3631a` Power Supply

class instruments.hp.HPe3631a(filelike)[source]

The HPe3631a is a three channels voltage/current supply. - Channel 1 is a positive +6V/5A channel (P6V) - Channel 2 is a positive +25V/1A channel (P25V) - Channel 3 is a negative -25V/1A channel (N25V)

This module is designed for the power supply to be set to a specific channel and remain set afterwards as this device does not offer commands to set or read multiple channels without calling the channel set command each time (0.5s). It is possible to call a specific channel through psu.channel[idx], which will automatically reset the channel id, when necessary.

This module is likely to work as is for the Agilent E3631 and Keysight E3631 which seem to be rebranded but identical devices.

Example usage:

>>> import instruments as ik
>>> psu = ik.hp.HPe3631a.open_gpibusb("/dev/ttyUSB0", 10)
>>> psu.channelid = 2           # Sets channel to P25V
>>> psu.voltage = 12.5          # Sets voltage to 12.5V
>>> psu.voltage                 # Reads back set voltage
array(12.5) * V
>>> psu.voltage_sense           # Reads back sensed voltage
array(12.501) * V

class Channel(parent, valid_set)[source]: Class representing a power output channel on the HPe3631a.

Warning

This class should NOT be manually created by the user. It is designed to be initialized by the HPe3631a class.

property channel

Gets a specific channel object. The desired channel is specified like one would access a list.

Return type:: HPe3631a.Channel

Hewlett-Packard

HP3456a Digital Voltmeter

HP6624a Power Supply

HP6632b Power Supply

HP6652a Single Output Power Supply

HPe3631a Power Supply

`HP3456a` Digital Voltmeter

`HP6624a` Power Supply

`HP6632b` Power Supply

`HP6652a` Single Output Power Supply

`HPe3631a` Power Supply