KMP_786C_B02 Page 4 of 4

www.murata-ps.com

786 Series

General Purpose Pulse Transformers

Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other

technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply

the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without

notice.

© 2008 Murata Power Solutions, Inc.

USA:

Mansfield (MA), Tel: (800) 233 2765, email: sales@murata-ps.com

Canada: Toronto, Tel: (866) 740 1232, email: toronto@murata-ps.com

UK:

Milton Keynes, Tel: +44 (0)1908 615232, email: mk@murata-ps.com

France:

Montigny Le Bretonneux, Tel: +33 (0)1 34 60 01 01, email: france@murata-ps.com

Germany: München, Tel: +49 (0)89-544334-0, email: ped.munich@murata-ps.com

Japan:

Tokyo, Tel: 3-3779-1031, email: sales_tokyo@murata-ps.com

Osaka, Tel: 6-6354-2025, email: sales_osaka@murata-ps.com

Website: www.murata-ps.jp

China:

Shanghai, Tel: +86 215 027 3678, email: shanghai@murata-ps.com

Guangzhou, Tel: +86 208 221 8066, email: guangzhou@murata-ps.com

Murata Power Solutions, Inc.

11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A.

Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356

www.murata-ps.com email: sales@murata-ps.com ISO 9001 REGISTERED

TUBE OUTLINE DIMENSIONS

0.60±0.15

(0.023±0.005)

4.00 (0.16)

5.50 (0.22)

10.95

(0.43)

12.95

(0.51)

3.80

(0.15)

15.70 (0.62)

Tube length: 465±2 (18.3±0.08). Tube quantity: 50.

Tube material: Antistatic coated clear pvc.

Unless otherwise stated all dimensions in mm (inches) ±0.25 (0.01).

TECHNICAL NOTES

ISOLATION

VOLTAGE

‘Hi Pot Test’, ‘Flash Tested’, ‘Withstand Volt-

age’, ‘Proof Voltage’, ‘Dielectric Withstand

Voltage’ & ‘Isolation Test Voltage’ are all terms

that relate to the same thing, a test voltage,

applied for a specified time, across a compo-

nent designed to provide electrical isolation, to

verify the integrity of that isolation.

All products in this series are 100% production

tested at their stated isolation voltage.

A question commonly asked is, “What is the

continuous voltage that can be applied across

the part in normal operation?”

For a part holding no specific agency approv-

als both input and output should normally be

maintained within SELV limits i.e. less than

42.4V peak, or 60VDC. The isolation test

voltage represents a measure of immunity to

transient voltages and the part should never

be used as an element of a safety isolation

system. The part could be expected to function

correctly with several hundred volts offset

applied continuously across the isolation bar-

rier; but then the circuitry on both sides of the

barrier must be regarded as operating at an

unsafe voltage and further isolation/insulation

systems must form a barrier between these

circuits and any user-accessible circuitry ac-

cording to safety standard requirements.

REPEATED HIGH-VOLTAGE

ISOLATION TESTING

It is well known that repeated high-voltage

isolation testing of a barrier component can

actually degrade isolation capability, to a

lesser or greater degree depending on ma-

terials, construction and environment. This

series has toroidal isolation transformers,

with no additional insulation between pri-

mary and secondary windings of enameled

wire. While parts can be expected to with-

stand several times the stated test voltage,

the isolation capability does depend on the

wire insulation. Any material, including this

enamel (typically polyurethane) is suscep-

tible to eventual chemical degradation when

subject to very high applied voltages thus

implying that the number of tests should be

strictly limited. We therefore strongly advise

against repeated high voltage isolation test-

ing, but if it is absolutely required, that the

voltage be reduced by 20% from specified

test voltage.

This consideration equally applies to agency

recognized parts rated for better than

functional isolation where the wire enamel

insulation is always supplemented by a

further insulation system of physical spacing

or barriers.