MR8740T_Quick guide_eng_20191016H.pdf - 第18页

12 Operation Precautions DANGER It is recommended to measure the secondary side of a distribution panel with the U8974 High V oltage Unit. Do not measure the primary side of the distribution panel because an unrestricted…

Operation Precautions

Rating of generator modules

You can mixedly install generator modules and measurement modules in the instrument.

Intended use Model name Number of

channels

Maximum output

frequency

Output voltage

For generating sine

wave and DC

Model MR8790

Waveform Generator

Unit

4 20 kHz −10 V to 10 V

For generating pulse

Model MR8791

Pulse Generator Unit

8 20 kHz

TTL level

(amplitude: 0 to 5 V)

Open-collector output

For generating DC

voltage, DC current,

and resistance

generation

Model U8794

VIR Generator Unit

Voltage: −0.1 V to 5.3 V

Current: −5 mA to 5 mA

Resistance: 10

to 1 M

Ratings of connection cords

Connection Cord Maximum input voltage Maximum rated voltage to earth

Model L9197 Connection Cord 600 V AC/DC

600 V AC/DC (CAT III)

300 V AC/DC (CAT IV)

Model L9198 Connection Cord

(for measuring low-voltage)

300 V AC/DC

600 V AC/DC (CAT II)

300 V AC/DC (CAT III)

Model L9217 Connection Cord

Model L9790 Connection Cord 600 V AC/DC

• With Model L9790-01 Alligator Clip or

Model 9790-03 Contact Pin attached

600 V AC/DC (CAT II)

300 V AC/DC (CAT III)

• With Model 9790-02 Grabber Clip

attached

300 V AC/DC (CAT II)

150 V AC/DC (CAT III)

Model 9322 Differential Probe

2000 V DC

1000 V AC

• With grabber clips attached

1500 V AC/DC (CAT II)

600 V AC/DC (CAT III)

• With alligator clips attached

1000 V AC/DC (CAT II)

600 V AC/DC (CAT III)

Model L4940 Connection Cord 1000 V DC*

• With Model L4935 Alligator Clip Set or

Model L4932 Test Pin Set attached

600 V AC/DC (CAT IV)

1000 V AC/DC (CAT III)

• With Model 9243 Grabber Clip or

Model L4936 Bus Bar Clip Set attached

600 V AC/DC (CAT III)

• With Model L4937 Magnetic Adapter

Set attached

1000 V AC/DC (CAT III)

• With Model L4934 Small Alligator Clip

Set attached

300 V AC/DC (CAT III)

600 V AC/DC (CAT II)

Model P9000-01 Differential Probe

1000 V AC/DC 1000 V AC/DC (CAT III)

Model P9000-02 Differential Probe

Model 9166 Connection Cord

30 V AC

60 V DC

For inputting voltage into Model U8979

*: When Model U8974 High Voltage Unit is used

Operation Precautions

DANGER

It is recommended to measure the secondary side of a distribution panel with

the U8974 High Voltage Unit. Do not measure the primary side of the distribution

panel because an unrestricted current ow could damage the instrument and

facilities if a short circuit occurs.

• Each channel of Model U8979 Charge Unit has the BNC terminal and miniature

connector terminal with the common ground. Do not connect cables with each

of the terminals simultaneously to avoid a short-circuit.

WARNING

• To avoid an electric shock and damage to the module and the instrument,

conrm that the instrument is turned off and that the connection cords are

disconnected before removing or replacing a module.

• To avoid an electric shock, install a blank panel over any slot with a module

removed.

• To prevent the instrument damage or an electric shock, use only the screws that

are originally installed for securing the module in place. If you have lost any

screws or nd that any screws are damaged, please contact your authorized

Hioki distributor or reseller.

CAUTION

• Do not touch module connectors inserted to the instrument to avoid damaging a

module.

• To avoid damage to the instrument, do not unplug the power cable from the

instrument when operations are in progress. Be sure to use the power key to turn off

the instrument.

• The U8794 permits a load resistance of 1 k

or more while outputting a voltage. Do

not connect a load resistance lower than the permissible value or short-circuit an

output terminal. Damage to the instrument could result.

• Do not set the OUTPUT terminal status of the U8794 to SHORT when a power supply

unit connects with the OUTPUT terminal. A short-circuit current will ow, resulting in

damage to the instrument or power supply device.

• Do not connect anything with the U8794 OUTPUT terminal during a general test

of the self-diagnosis function and an offset measurement of the offset canceling

function. When the connected target is a power supply device, the instrument and the

connected target can be damaged because the OUTPUT terminals of each channel

are momently short-circuited.

• The mounting screws must be rmly tightened or the module may not work as

specied, or may even fail.

• When you use the U8794 resistance generation function to presume a characteristic

of a connected target with an output resistance of less than 1 k

, a current that

exceeds the specication will ow, resulting in damage to the instrument and the

connected target.

• Model U8979 Charge Unit has two miniature connectors with the maximum input

charge of ±500 pC (for six higher-sensitivity range) or ±50,000 pC (for six lower-

sensitivity range). Inputting a charge that exceeds these value causes damage to the

instrument.

• Use an acceleration sensor with a built-in pre-amplier that conforms to the

specication of Model U8979 (3.5 mA, 22 V). Using a inapplicable sensor may cause

damaging itself.

Operation Precautions

IMPORTANT

• Install a blank panel over the slot with no module installed. If the measurement is performed

without the blank panel installed, the instrument may not work as specied because of

temperature instability within the modules.

• If any unexpected waveform is observed or a module is not recognized, send the instrument for

repair.

• Disconnect all cables and remove a USB ash drive before carrying the instrument.

• Waveforms can frequently uctuate even when no voltage is applied due to an induction voltage.

This, however, is not a malfunction.

• This instrument may cause interference if used in residential areas. Such use must be avoided

unless the user takes special measures to reduce electromagnetic emissions to prevent

interference to the reception of radio and television broadcasts.

Precautions during shipment

CAUTION

To avoid damage to the instrument, protect it from physical shock when transporting

and handling. Be especially careful to avoid physical shock due to dropping it.

• Store the packaging materials even after unpacking, because you will need them when you

transport the instrument.

• To ensure safe handling, when transporting the instrument, please use the original box and

packing materials,

but do not use if the box is damaged or warped, or if the packing materials are in poor condition

or incomplete.

If you nd any damage, contact your authorized Hioki distributor or reseller.

• When packing the instrument, make sure to disconnect the test leads and power supply cords

from the main device.

• When transporting, avoid dropping or other excessive impact.

CD precautions

• Exercise care to keep the recorded side of discs free of dirt and scratches. When writing text on a

disc’s label, use a pen or marker with a soft tip.

• Keep discs inside a protective case and do not expose to direct sunlight, high temperature, or

high humidity.

• Hioki is not liable for any issues your computer system experiences in the course of using this

disc.