BRUEL & KJAER 2825 User manual

Brüel&Kjær
BI5033–12e
Technical
Documentation
WORLD HEADQUARTERS: DK-2850 Nærum • Denmark •
Telephone: [phone] •Telex: 37316 bruka dk • Fax: [phone] •
e-mail: [e-mail]
Acquistion Front-end
Type 2825
Service Manual

0−2Brüel & KjærAcquisition Front-end Type 2825
Service Manual
Proprietary: Authorized Brüel & Kjær Personnel Only

April 1997
BI5033–12e
Brüel & Kjær Acquisition Front-end Type 2825
Service Manual
Acquisition Front-end
Type 2825
Service Manual
Valid from serial number 1 904 567

0−2Brüel & KjærAcquisition Front-end Type 2825
Service Manual
Safety Considerations
This apparatus has been designed and tested in accordance with IEC Publication
348, Safety Requirements for Electronic Measuring Apparatus, and has been supplied
in safe condition. This Guide contains information and warnings which must be fol-
lowed by the user to ensure safe operation and to retain the apparatus in safe
condition. Special note should be made of the following:
Safety Symbols
See the associated warning statements given in the User Guide.
Chassis Terminal
Safety Earth Terminal
Hazardous Voltage
Warnings
This is a CISPR II, Class A product. In a domestic environment this product may
cause radio interference in which case the user may be required to take adequate
measures
Switch off all power to equipment before connecting or disconnecting their digital
interface. Failure to do so could damage the equipment.
Whenever it is likely that the correct function or operating safety of the apparatus
has been impaired, it must be made inoperative and be secured against unintended
operation.
Any adjustment maintenance and repair of the open apparatus under voltage must
be avoided as far as possible and, if unavoidable, must be carried out only by trained
service personnel.
Copyright © 1997, Brüel&Kjær Sound and Vibration Measurement A/S
All rights reserved. No part of this publication may be reproduced or distributed in
any form or by any means without prior consent in writing from Brüel & Kjær Sound
and Vibration Measurement A/S, Nærum, Denmark.

Acquisition Front-end Type 2825
Service Manual
BI5033–12e 0−3
Contents
1. General Information.................................................................................................. 1–1
1.1 Introduction................................................................................................................. 1–2
1.2 Edition Number........................................................................................................... 1–2
1.3 Safety ........................................................................................................................... 1–3
1.4 Service Policy and FRP Number ................................................................................ 1–3
2. Service Note...................................................................................................................... 2–1
2.1 On-line Editions of the Service Manual..................................................................... 2–2
2.2 Printed Editions of the Service Manual..................................................................... 2–2
3. Checking Procedure................................................................................................... 3–1
3.1 Introduction................................................................................................................. 3–2
3.2 Checking Procedure .................................................................................................... 3–2
3.3 Test of ventilator......................................................................................................... 3–2
4. Adjustment Procedure............................................................................................. 4–1
4.1 Introduction................................................................................................................. 4–2
4.2 Procedure..................................................................................................................... 4–2
5. Troubleshooting............................................................................................................. 5–1
5.1 Introduction................................................................................................................. 5–2
5.2 Procedure..................................................................................................................... 5–2
5.3 Cooling fan................................................................................................................... 5–2
6. Routine Maintenance................................................................................................ 6–1
6.1 Routine Maintenance.................................................................................................. 6–2
Cleaning of Air-filter .............................................................................................. 6–2

Acquisition Front-end Type 2825
Service Manual Brüel & Kjær
0−4
7. Mechanical Parts.......................................................................................................... 7–1
7.1 Dismantling Procedure............................................................................................... 7–2
Removing the Power Supply.................................................................................. 7–2
Removing the Backplane ....................................................................................... 7–3
7.2 Mains Switch and Fuseholder.................................................................................... 7–3
7.3 Fan Assembly UH1022............................................................................................... 7–4
7.4 Mechanical Parts List................................................................................................. 7–4

Acquisition Front-end Type 2825
Service Manual
BI5033–12e 1−1
Chapter 1
General Information

Chapter 1 — General Information
Introduction
Acquisition Front-end Type 2825
Service Manual Brüel & Kjær
1−2
1.1 Introduction
Acquisition Front-end Type 2825 is a frame for housing modules for use in Type
3550, Type 3551 and Type 3560 (PULSE) systems.
1.2 Edition Number
If any major changes are made to the instrument and/or Service Manual, a new
edition of the Service Manual will be released. Any new edition can be recognised
by the Literature Number (BI5024-xx) given at the bottom of odd numbered pages.
The serial number from which each edition is valid is printed in the Frontispiece of
this Service Manual.
Fig.1.1 Type 2825

Chapter 1 — General Information
Safety
Acquisition Front-end Type 2825
Service Manual
BI5033–12e 1−3
Information concerning minor changes will be released in the form of a Service
Note which is dealt with in section 2.1.
1.3 Safety
Type 2825 has been designed and tested in accordance with IEC Publication 348,
Safety Requirements for Electronic Measuring Apparatus, and has been supplied in
safe condition.
Any work done on the instrument when open must be done by a qualified person
who is aware of the hazards involved.
Note: The word WARNING denotes a hazard. It calls attention to a procedure,
practice, or like, which, if not correctly performed or adhered to, could result in
personal injury.
1.4 Service Policy and FRP Number
Type 2825 itself is not a Field Replaceable Part (FRP). If any of the mechanical
parts in Type 2825 fail, they need to be replaced as spare parts. See Chapter 7 for
more details.
The ZG0391 power supply in Type 2825 is an FRP. To assure economical reuse, it is
important that no attempt is made to repair it locally. If such an attempt is made,
the price of an exchange FRP is 100% the price of a new one.
Therefore, DO NOT ATTEMPT ANY REPAIR to ZG0391. If a fault is found,
order an FRP under number FR0173.

Chapter 1 — General Information
Service Policy and FRP Number
Acquisition Front-end Type 2825
Service Manual Brüel & Kjær
1−4