JA972

B3-38A

B3-38A or V3-38A Russian Millivoltmeter

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This repository contains all the collected informations regarding the old russian millivoltmeter instrument. The goal to collect datasheets, schematics, etc.

BOM, Service Manual

Technical characteristics

Millivoltmeter V3-38A (V3 38A, V338A, b3-38a, b338a, b3 38a)

Designed to measure the rms AC voltage sine wave of 0.1 mV to 300 V in the frequency range from 20 Hz to 5 MHz. The span value of 1 mV, 3mV, 10mV, 30mV, 100mV, 300mV, 1V, 3V, 10V, 30V, 100V and 300V The basic error of ± 2,5%

Millivoltmeter V3-38A is designed to measure the rms AC voltage sine wave of 0.1 mV to 300 V in the frequency range from 20 Hz to 5 MHz. The operating conditions of use of the instrument Millivoltmeter V3-38A: ambient temperature from 10 ° to 35 ° C; relative humidity. air 80% at 25 ° C, atmospheric pressure from 86 to 106 kPa (650 to 800 mm Hg. st.) mains (220 ± 22), frequency (50 ± 0,5) Hz . Technical Data is a Measurement range of the instrument voltages from 300V to 100mkV overlapping ranges with upper limits of 1 mV, 3mV, 10mV, 30mV, 100mV, 300mV, 1V, 3V, 10V, 30V, 100V and 300V. Instrument measures the voltage in the frequency range from 20 Hz to 5 MHz . The range of frequencies of the device Millivoltmeter V3-38A has a working range of frequencies: I from 45 Hz to 1 MHz (on); II from 20 to 45 Hz (except); III St.. 1 to 3 MHz (on); IV St.. 3 to 5 MHz (inclusive). Frequency of calibration of 1 kHz. Primary instrument error, expressed as a percentage of the upper limit established by sub-band measurements, no more than ± 2,5%. Instrument error Millivoltmeter V3-38A in the working frequency regions, expressed as a percentage of the upper limit of the established sub-band, and the change of readings within the operating frequency ranges with respect to the frequency of calibration readings in percent, do not exceed the values shown in Table. 1.

Table 1: The limits of permissible errors (beyond the assumed changes of reading),%

Change readings, caused by changes in temperature. Ambient air from the normal to any temperature within the operating temperature range does not exceed the basic error for every 10 ° C change in temperature. Change readings Millivoltmeter V3-38A, expressed as a percentage of the upper limit established by sub-band, rejecting the shape of the measured voltage from the sinusoidal (THD less than 20%) is less than half the value of the harmonic content in percent. The deviation of the index from scratch, due to the intrinsic noise does not exceed 5% of the upper limit established by sub-band measurements with closed-circuit input. The device retains its specifications within the rules, if its input DC voltage is not more than 250-V Response time the device is less than 4 seconds. Millivoltmeter V3-38A save tons of basic error handling five times after exposure to stress, but not more than 600 V. Active impedance device, measured at a frequency of 45 Hz, less than 5 megohms at subbands upper limits 1-300mV and at least 4 Mohms subbands upper limits in 1-300 Input capacitance unit is not more than 25 pF subbands upper limits of 1-300 mV and not more than 15 pF subbands upper limits of 1-300 W. The capacity of each of the connecting cable is not more than 80 pF. Warm-up time 15 min. Millivoltmeter V3-38A retains its specifications when powered from the mains AC voltage (220 ± 22) V (50 ± 0,5) Hz. The power consumed by the network at a nominal voltage not exceeding 6 VA. Device allows continuous operation in the working conditions for 8 hours

Unit weight Millivoltmeter V3-38A or less than 3.2 kg.