1. Introduzione
The Brother HD-390A+ is a high-precision analog multimeter designed for electricians, home maintenance, and general electrical testing. It offers a wide range of measurement capabilities including DC voltage, AC voltage, DC current, resistance, battery testing, transistor hFE, diode, decibel, and continuity checks. This manual provides essential information for safe and effective use of your multimeter.
2. Informazioni sulla sicurezza
- Prima di collegare il multimetro a un circuito, assicurarsi sempre che sia impostato sulla funzione e sull'intervallo corretti.
- Non tentare di misurare il voltages or currents exceeding the specified maximum ratings of the device.
- Prestare la massima cautela quando si lavora con circuiti sotto tensione. Siate sempre convinti che i circuiti siano sotto tensione fino a prova contraria.
- Inspect test leads for any damage (e.g., cracked insulation, exposed metal) before each use. Replace damaged leads immediately.
- Replace batteries and fuses only with the specified types and ratings to maintain safety and performance.
- Non utilizzare il multimetro se appare danneggiato o non funziona correttamente.
3. Impostazione
3.1 Installazione della batteria
The HD-390A+ multimeter requires two AAA 1.5V batteries and one 9V battery for operation. Batteries are not included with the device.
- Individuare il vano batteria sul retro del multimetro.
- Open the battery cover by pulling down and opening as indicated on the cover.
- Insert the two AAA 1.5V batteries and one 9V battery, ensuring correct polarity (+/-) as marked inside the compartment.
- Chiudere bene il coperchio della batteria.
Visual reference for battery compartment:
Indietro view of the Brother HD-390A+ multimeter, highlighting the battery cover.
3.2 Collegamento dei puntali di prova
- Inserire il puntale di prova nero nel jack 'COM' (comune).
- Per la maggior parte delle misurazioni (voltage, resistance, low current), insert the red test lead into the 'VmAΩ+' jack.
- For high DC current measurements (up to 10A), insert the red test lead into the '+10A' jack.
Visual reference for test lead connection:
Davanti view of the multimeter with test leads connected to the appropriate jacks.
3.3 Zero Ohm Adjustment
Before measuring resistance, it is crucial to perform a Zero Ohm Adjustment to ensure accuracy.
- Set the rotary switch to any resistance (Ω) range.
- Short the red and black test leads together.
- Turn the 'Ω ADJ' knob (yellow knob) until the pointer reads exactly zero on the resistance scale. This compensates for internal battery voltage variazioni.
4. Istruzioni per l'uso
4.1 Oltreview dei controlli
The multimeter features a central rotary switch to select the measurement function and range, an 'Ω ADJ' knob for resistance calibration, and input jacks for test leads.
Davanti view of the Brother HD-390A+ multimeter, illustrating the main controls and display.
4.2 Reading the Analog Scale
The analog display features multiple scales for different measurement types. Always refer to the scale corresponding to the selected function and range on the rotary switch.
4.3 Procedure di misurazione
- Misurazione del volume CCtage (VCC):
- Set the rotary switch to the desired DCV range (0.1V, 2.5V, 10V, 50V, 250V, 1000V). Start with the highest range if the voltage è sconosciuto.
- Collegare il puntale di prova rosso al lato positivo del circuito e il puntale di prova nero al lato negativo.
- Read the value from the DCV scale.
- Misurazione del volume CAtage (ACV):
- Set the rotary switch to the desired ACV range (10V, 50V, 250V, 1000V). Start with the highest range if the voltage è sconosciuto.
- Collegare i puntali di prova attraverso la tensione CAtage fonte.
- Read the value from the ACV scale.
- Measuring DC Current (DCmA):
- IMPORTANTE: Prima di collegare il multimetro in serie, assicurarsi che il circuito sia disattivato.
- Set the rotary switch to the desired DCmA range (50uA, 2.5mA, 25mA, 250mA). For 10A, use the '+10A' jack and the 10A range.
- Interrompere il circuito e collegare il multimetro in serie con il carico.
- Re-energize the circuit and read the value from the DCmA scale.
- Misurazione della resistenza (Ω):
- IMPORTANTE: Ensure the circuit is de-energized and the component is isolated before measuring resistance.
- Set the rotary switch to the desired Ω range (X1, X10, X100, X1K, X10K, X100K).
- Short the test leads and perform a Zero Ohm Adjustment using the 'Ω ADJ' knob (see Section 3.3).
- Collegare i puntali di prova al componente.
- Read the value from the Ω scale and multiply by the range multiplier.
- Battery Check (BATT):
- Set the rotary switch to the 1.5V or 9V BATT range.
- Collegare il puntale di prova rosso al terminale positivo della batteria e il puntale di prova nero al terminale negativo.
- Read the battery condition (GOOD, ?, BAD) from the BATT scale.
- Transistor hFE Check:
- Impostare il selettore rotante sulla gamma hFE.
- Insert the transistor leads into the appropriate NPN or PNP sockets.
- Leggere il valore hFE.
- Controllo diodo:
- Set the rotary switch to the Diode Check range (via Test Leads).
- Collegare i puntali di prova al diodo.
- Observe the reading to determine forward voltage drop or open circuit.
- Decibel (dB) Measurement:
- Set the rotary switch to an ACV range.
- Read the dB value from the dB scale.
- Controllo di continuità:
- Set the rotary switch to the Rx1 range.
- If the resistance is less than approximately 200 Ohms, a beeper will sound.
4.4 Dimostrazione video
Watch this video for a practical demonstration of the Brother HD-390A+ multimeter's basic functions, including resistance and voltage misurazioni.
Video demonstrating the operation of the Brother HD-390A+ Analog Multimeter.
5. Manutenzione
5.1 Sostituzione della batteria
When the pointer does not zero correctly during resistance measurement, or the battery check indicates low power, it's time to replace the batteries. Follow the steps outlined in Section 3.1, 'Battery Installation'.
5.2 Sostituzione del fusibile
If the multimeter fails to measure current or shows an open circuit on a known good circuit, the fuse may be blown. The device is protected by Fuses 0.5A/250V and 10A/250V (for the 10A range). Fuse replacement should ideally be performed by qualified personnel. Always replace with fuses of the exact same type and rating.
5.3 Pulizia
Pulisci il multimetro casing with a dry, soft cloth. Do not use abrasive cleaners, solvents, or immerse the device in water.
5.4 Conservazione
Store the multimeter in a cool, dry place, away from direct sunlight, extreme temperatures, and high humidity. Remove batteries if storing for extended periods to prevent leakage and damage.
6. Risoluzione Dei Problemi
- No Reading/No Pointer Movement:
- Check if the multimeter is turned ON (rotary switch not in OFF position).
- Ensure test leads are correctly inserted and not damaged.
- Verify battery charge; replace if necessary.
- Check for blown fuses, especially for current measurements.
- Assicurarsi che il selettore rotativo sia impostato sulla funzione e sull'intervallo corretti.
- Lettura errata:
- Verify the correct range is selected for the measurement.
- Perform Zero Ohm Adjustment for resistance measurements.
- Ensure good, clean contact between test leads and the circuit/component.
- Verificare la presenza di interferenze elettriche esterne.
- Il cicalino non suona (continuità):
- Ensure the rotary switch is set to the Rx1 range.
- Confirm that the resistance of the circuit being tested is below approximately 200 Ohms.
7. Specifiche
The following tables detail the technical specifications of the Brother HD-390A+ Analog Multimeter:
Specifiche generali
- Dimensioni: 160mm * 105mm * 40mm
- Standard Environmental Conditions: 23°C ± 5°C, humidity <75% RH
- Working Environment Range: 0°C ~ 40°C, humidity <90% RH
- Alimentazione elettrica: R03P, AAA, 1.5V x2pcs (for Ω, Buzzer, hFE, Diode testing); 6F22 NEDA1604 9V x 1pc (just for Ω(Rx10k) testing).
- Protezione: Full protection.
Specifiche di misurazione
| Funzioni di prova | Allineare | Precisione | Osservazioni |
|---|---|---|---|
| Corrente continua V | 0-0.1-2.5-10-50-250 V -1000 V | ±3% FSD. ±4% FSD. For 1000V | Input Impedance: 20KΩ/V Overload Protection: Max. 1000V AC/DC BUT 0.1V/2.5V/10V 250V Max. |
| ACV | 0-10-50-250V -1000 V | ±4% FSD. ±5% FSD. For 1000V Band width: 40 ~ 10K Hz | Input Impedance: 9KΩ/V Overload Protection: Max. 1000V AC/DC But 10V/50V only 250V Max. |
| Corrente continua mA | 0-0.05-2.5-25-250 mA, 10A | ±3% FSD. ±4% FSD. For 10A | Goccia voltage: 250 mV Overload protected by Fuses 0.5A/250V & 10A/250V at 10A range Max. testing time |
| Funzioni di prova | Allineare | Precisione | Osservazioni |
|---|---|---|---|
| Ω | X 1: 0.2 ~ 2KΩ Midscale at 20Ω X 10: 2 ~ 20KΩ Midscale at 200Ω X 100: 20 ~ 200KΩ Midscale at 2000Ω X1K: 200 ~ 2MΩ Midscale at 20KΩ X10K: 2K ~ 20MΩ Midscale at 200KΩ X100K: 20K ~ 200MΩ Midscale at 2000KΩ | ±3% of ARC of Scale Length | Protected by the extra Thermal Resettable Fuse <250V AC/DC. Powered by AAA 1.5V x2pcs & block 9V battery x1pc. |
| Capacità (uF) | 0.025-0.25-25uF(C2 50uA), 2000uF(C1) | ±3% FSD. Approximate Value | Use the Accessory Kit Use the R x 1K range |
| Controllo BATT | 0 ~ 1.5V: GOOD ? - BAD 0 ~ 9V: GOOD ? - BAD | ±5% of ARC of Scale Length | Load Current: 270mA for 1.5V 25mA for 9V Overload protected by Fuse & Oxide Varactor <250V (5s). |
| Transistor, LED hFE Check | hFE: 0-1000 via special hFe socket Check | Valore approssimativo | At Ω X 10 Range |
| Controllo diodi | via Test Leads | Valore approssimativo | At Ω X 10 Range |
| Decibel | -22 dB ~ + 62 dB (0dB=1mW at 600Ω) | Valore approssimativo | A intervalli ACV |
| Controllo di continuità | •))) At Rx1 range | Beeper sounding <200 Ohm approx. | Protected by the Resettable Fuse & Oxide Varactor <250V (5s). |
8. Suggerimenti per l'utente
- Always start with a higher range when measuring an unknown value to prevent overloading the meter and ensure safety.
- For resistance measurements, ensure the component is isolated from the circuit to get an accurate reading.
- Keep the test leads organized and free from tangles to avoid damage and ensure quick setup.
- Considera l'acquistoasing a spare set of fuses and batteries to minimize downtime during critical tasks.
9. Garanzia e supporto
For warranty information, technical support, or service inquiries, please contact the original seller or manufacturer directly. Please retain your purchase receipt as proof of purchase for any warranty claims.
