B&K Precision 307A User Manual

Instruction Manual

Model 307A Analog Insulation & Continuity Meter

Index Page

Safety Precautions........................................ 1

Safety Notes................................................. 2

Features ...................................................... 2-3

Connections ................................................ 3

Specifications ...... ....................................... 4

Why Test is necessary ................................. 5

Instrument Layout ........................................ 6

Lid Instruction Label .................................... 7

Preparation for Measurement ..................... 8

Functions .............................. ...................... 8-14

Battery & Fuse Replacement ....................... 15

Calibration & Servicing ................................. 16

Cleaning & Storage....................................... 16

Limited One-year Warranty
Service Information

....................................... 18

YOUR COMMENTS ARE IMPORTANT TO US

We have become a market leader in test and

measurement in recent years, due to the company's

ability to design and bring to the market innovative
instruments and devices which offer real customer

benefits. The cornerstone of this ability is the

company's focus on customer requirements

and the emphasis placed on end-user satisfaction.

We appreciate customer information and requirement

to improve or design new products.

........................... 17

1. Safety Precautions

Electricity can cause severe injuries even with low voltages or
currents.
Therefore it is extremely important that you read the following
information before using your Analog Insulation Tester.

1.1 This Instrument must only be used and operated by a competent
trained person and in strict accordance with the instructions.
We will not accept liability for any damage or injury caused by
misuse or non compliance with instructions and safety procedures.

1.2 This Instrument must not be used on live circuits. Ensure all circuits
are de-energised before testing. See paragraph 1.8 for details of
built-in warning features should your Analog Insulation tester be
connected to a live system.

1.3 Never open Your Analog Insulation Tester except for battery
replacement. (See Battery replacement section).

1.4 Always inspect you Analog Insulation tester and test leads before
use for any sign of abnormality or damage. If any abnormal
conditions exist (broken test leads, cracked case, display faulty
etc...) do not attempt to take any measurement or use the tester.
Return your Analog Insulation tester to your nearest Distributor
for Service.

1.5 Never replace the protective fuse with any other than the specified
or approved equivalent.

1.6 Your Analog Insulation tester has been designed with your safety
in mind. However, no design can completely protect against
incorrect use. Electrical circuits can be dangerous and/or lethal
when a lack of caution or poor safety practice is used. Use caution
in the presence of voltage above 24V as these pose a shock hazard.

1.7 Pay attention to cautions and warnings which will inform you of
potentially dangerous procedures.

1.8 Your Analog Insulation Tester has a live circuit warning bleeper.
If it is connected to an AC live circuit, a beep of twice the frequency
of the voltage present will be heard.
DO NOT proceed to test and immediately disconnect the instrument
from the circuit. In addition, the warning light will lit if the voltage is
above 100Vdc or 70Vac.
When AC voltage is present, before testing, it's value is displayed
on the AC scale.

-1-

2. Safety Notes

Rated environmental conditions
(1). Indoor use.
(2). Installation Category .
(3). Pollution Degree 2.
(4). Altitude up to 2000M

Meter is protected throughout by double
insulation or reinforced insulation.

Warning ! Risk of electric shock.

Caution ! Refer to this manual before using the
meter.

3. Features

Ÿ

High Quality Taut Band movement.

Ÿ

Three Insulation test voltages
1- 250Vdc -100MW

2- 500Vdc -200MW
3- 1000Vdc -400MW

Ÿ

Two Continuity Test on Low Ohms 500W & 3W

Ÿ

Designed to meet IEC 1010-1 safety standard..

Ÿ

Small and Lightweight, all in one case (do not need bag).

Ÿ

AC voltmeter with linear scale up to 600Vac.

Ÿ

200mA continuity short circuit current.

Ÿ

1mA test current on Insulation Test at nominal voltage.

Ÿ

Automatic discharge of capacitance and inductive
circuit with charge stored in the circuit under test.

Ÿ

Live Warning and display of external voltage presence.

Ÿ

Fuse, Air Gap, Crowbar and Overload Protected.

Ÿ

On line battery monitoring shows if battery is ok..

-2-

Auto null of the test leads on continuity tests.

Ÿ

Very Low Battery Consumption.

Ÿ

On-Load battery check (+/-205mA load for worst case)

Ÿ

operates on 8 dry batteries (AA, R6P type..)
Mirror scale.

Ÿ

Push and Turn locking switch for long and hand free

Ÿ

testing.
Designed to meet international standards.

Ÿ

Supplied with High Quality test leads.

Ÿ

4. Connections

!

CAT. III

LINE

MAX 600V

EARTH

-3-

5. Specifications

INSULATION

Test Voltage 250Vdc 500Vdc 1000Vdc

+10%-0% +10%-0% +10%-0%
Mirror scale 100MW 200MW 400MW
Mid Scale 1MW 2MW 4MW

Scale Multiplier x1/2 x1 x2
Accuracy ±3%
Output Short-Circuit Current 1.3mA
Regulated Output Voltage (up to 1mA current)

263.5V / 525V / 1052V

CONTINUITY

Low W 0 - 3W 0 - 500 W
Test Leads / Fuse Zero W Adjustment by knob
Output Short-Circuit Current 205mA
Accuracy ±1.5% of scale length

AC Voltage

Range 0 - 600Vac
Accuracy ±3% of scale length

Voltage Warning

Warning Light Circuit Live lit from 90Vdc / 70Vac
Buzzer Beep from 24Vac / dc

Battery Check

Battery Check indicate good batteries from 8Vdc to 13Vdc
during a Load test of 205mA.

Battery OK

Battery OK Led lit from 8Vdc and is operative while testing.

-4-

6.Why test is necessary ?

INSULATION

Every electrical apparatus and installation need to be safe
for the user and for the equipment itself.
Electrical conductors of electricity need to be insulated
from each other, so that they do not create electrical
hazard or unnecessary consumption.
Badly insulated circuits can create leakage current which
can be dangerous and trip your GFCI, RCCB or ELCB..
Each country regulate those levels at which the insulation
is acceptable.
Generally, Insulation resistance measurements are done
between each conductor and the earth, and between
each conductors.

CONTINUITY

Checking the continuity of wires, complete circuits,
connections, closure of contacts, circuit breakers, fuses,
bounding resistance of connections, etc... Are all very
important.

-5-