Lufft CHM 8k User manual

General Information - 1 -
User Manual
Lufft CHM 8k Ceilometer

General Information 2
Contents
 .......................................................................................................................
 ............................................................................................................................
 .............................................................................................................................................
  ..........................................................................................................
  ....................................................................................
 ................................................................................................
  .............................
 .......................................................................................................
  ................................................................................................
 ...................................................................................
  ..........................................................................................................
  .........................................................................................................................
 ................................................................................................................................
  .................................................................................................................
 ...........................................................................................................................
 ................................................................................................................. 
  ................................................................................................... 
  ..................................................................................... 
 ................................................................................................................. 
  ........................................................................................ 
..................................................................................................... 
 ................................................................................................................................... 
 ............................................................................................................. 
  .................................................................................................................... 
 .................................................................................................... 
  .............................................................................................................. 
 .................................................................................... 
  .................................................................................. 
  ...................................................................................... 
  ............................................................................................................................... 
  ................................................................................................................................. 
 ...................................................................................... 
 .............................................................................................. 
  ........................................................................................... 
  ....................................................................................................... 
 ................................................................................................................ 
 .......................................................................................................... 
  ..................................................... 
 ..................................................................................................... 
 .................................................................................................................. 
  .......................................................................................................................... 
  .......................................................................................................... 
  ......................................................................................................... 
  ......................................................................................................... 
  ................................................................................................................. 
  ...................................................................................................... 

 R1.7 / 01-2020
General Information 3
  ............................................................................................. 
  .................................................................................................................................. 
  ...................................................................................................................... 
 .............................................................................................................................. 
  ..................................................................................................................... 
 ......................................................................... 
  ............................................................................................................................ 
  .......................................................................................................... 
  .................................................................................................................... 
  ........................................................................... 
  ................................................................... 
  ............................................................ 
  ..................................................................................... 
  ......................................................................... 
  ............................................................................................................................ 
  .............................................................................................................................. 
 ............................................................................................................ 
 .................................................................................................................... 
 ................................................................... 
 ............................................................................................................. 
  ......................................................................................... 
  ....................................................................................... 
 ....................................................................................................... 
 .............................................................................................. 
 ......................................................... 
 ............................................................................................... 
  .............................................................................................................. 
  ................................................................................................................. 
  ...................................................................................................... 
  ..................................................................................................... 
  .................................................................... 
  ................................................................................................................................. 
  .................................................................................... 
 ....................................................................................................................................... 
  .......................................................................................... 
  ....................................................................................................... 
 ........................................................................................................................... 
  ............................................................................................................................ 

General Information 4
1 
This operating manual is part of the equipment. It must always be kept close
to the equipment so that it can be accessed quickly when needed.
This operating manual must be read, understood and observed in all respects
by all persons responsible for the equipment and all persons who work on it.
This applies, in particular, to the chapter "Safety".
Editorial deadline: January 2020
Documentation number: 8349.MEP
This operating manual is valid for the following versions of the equipment with the order numbers:
8349.01-010
8349.11-010
8349.11-003
8349.21-010
8349.31-010
8349.02-010
8349.12-010
8349.22-010
8349.32-010
The description of the DSL modem is given in a separate supplementary sheet.
Manufacturer
G. Lufft Mess- und Regeltechnik GmbH
Gutenbergstraße 20
70736 Fellbach, Germany
Phone [phone] 831
E-mail [e-mail]
Date
Issue
Notes
July 2018
R1
Initial release
February 2019
R1.4
Revision, adaptation to new firmware
October 2019
R1.6
Revision chapter 10, technical data, safety advise,
adaptation to new firmware
January 2020
R1.7
Revision, adaptation to new firmware
Copyright
© 2020
This manual is protected by copyright. No part of this manual may bereproduced in any form (photograph,
photocopy, microfilm or any other method) or processed, duplicated or distributed using electronic
systems without the written permission of G. Lufft GmbH. Violations will be prosecuted.
The manual was prepared with due care. No liability is assumed for damages resulting from failure to
observe the information contained in the manual.

 R1.7 / 01-2020
Safety 5
1.1 Symbols used
Remarks for the smooth use of the equipment
Required action step
2 
2.1 Standards and Directives
The device is designed according to the recognized rules of technology and safety and is manufactured
in series unchanged. The applied rules are listed in the currently valid declaration of conformity.
Declarations of conformity can be downloaded from our homepage:
https://www.lufft.com/products/cloud-height-snow-depth-sensors-288/lufft-ceilometer-chm8k-2405/
In Europe, the declaration of conformity is enclosed in the accompanying documents.
2.2 Safety instructions for the laser system
The  Ceilometer is classified as a Class 1M laser product according to IEC 60825-1:2014-05. It
complies with 21 CFR 1040.10 except for deviations pursuant to Laser Notice No. 50, dated June 24,
2007. The sensor emits a beam of invisible laser radiation (905 nm) with small divergence (< 1.5 mrad)
and a beam diameter of 60 mm (FWHM). A warning label is attached to the front of the instrument (see
section 2.6).
Class 1M radiation is regarded safe except when viewed with telescope optics. The instrument may only
be operated in a protected outside area. The following precautions must be taken when operating the
sensor:
•Never view the laser beam with optical instruments, especially binoculars
•Avoid looking directly into the laser beam
•Do not operate the instrument with the inner sensor door open
•Do not operate the sensor horizontally (maximum tilt angle 20°)
•Keep the beam path free of reflecting materials
The laser radiation emitted by the sensor is generated by an embedded Class 3B laser module. Even
short exposure to Class 3B laser radiation can lead to injuries to the eye and skin. Maintenance and
service of the sensor may only be carried out by trained personnel. Under no circumstances may the
laser module be removed from the measuring unit or any protective covers removed!
2.3 Requirements for the personnel
•The  may only be installed and commissioned by trained personnel who have received
instructions in safety-related matters. Electrical connection of the device may only be carried out
by a qualified electrician.
•Maintenance and adjustment work on the  may only be carried out by the service staff of
G. Lufft GmbH or by   authorized and trained personnel. All maintenance work
requires a technical qualification in electrical safety.
•Every person assigned to install and commission the  must have read and understood
the complete user manual.
•During all work on the equipment, personnel must not be overtired and must not be under the
influence of alcohol, medicines or intoxicants. The personnel must have no physical limitations
that temporarily or permanently restrict their attention and judgment.
2.4 Safety instructions for transport, installation, commissioning and cleaning
•The  may only be loaded and transported in the packed condition and in the transport
position (see Figure 5) using suitable lifting gear and transport equipment.
•Inside the shipping container/truck the  must be adequately protected against slipping,
shock, or other mechanical impacts, e.g. by using straps.
•If the  is not installed immediately, it must be stored protected from external influences
and adequately secured.
•At least two people are required to install the .

 R1.7 / 01-2020
Safety 6
•Once the  has been installed, it must be checked. Make sure that no safety-related
changes have taken place on the device.
•The inner housing door may only be opened by the service staff of G. Lufft GmbH or by the

•Never operate the sensor if a cover window is broken. Return the sensor to G. Lufft GmbH for
repair.
•Explosion hazard. Do not install the CHM 8k in hazardous locations.
2.5 Description of the warnings
2.5.1 Description of warning symbols
Symbol
Use
Warning of a general hazard
Warning of laser beam
Warning of dangerous electrical voltage
Warning of hot surface
Electrical equipment marked with this symbol may not be
disposed of in European domestic or public disposal systems.
Return old or end-of-life equipment to the manufacturer for
disposal at no charge to the user.
2.5.2 Description of precautionary statements
WARNING
Indicates a hazardous situation that, if not avoided, could result in death or serious injury.
CAUTION
Indicates a hazardous situation that, if not avoided, could result in minor or moderate injury.
NOTICE
Indicates a situation which, if not avoided, may cause damage to the instrument. Information that
requires special emphasis.

 R1.7 / 01-2020
Safety 7
2.6 Product labeling 8k
The product labels are show in Figure 1. The type plate and the protective earth connection are located
on the back of the housing foot.
Figure 1 Safety labeling.
2.7 Designated use
The operational safety of the CHM 8k is only guaranteed if used as designated in accordance with the
instructions in this operating manual.
The device is designed for single phase operation on a public low-voltage network in accordance with
IEC38, 6th edition, 1983.
The ceilometer may be used only in a protected outside area. In standard operation, the laser beam is
aligned to the zenith, i.e. the device measures vertically. It can be tilted with adequate accessories to a
maximum tilt angle of 20°. Any use beyond this limit is considered non-designated use! The operator
bears sole responsibility for any resulting damage.
Horizontal use represents a safety risk for third parties and is expressly excluded.
For trouble-free operation, follow a regular cleaning and maintenance cycle (see chapter 10).
Never operate the sensor if a cover
window is broken! Refer to section 10
for a detailed explanation.

 R1.7 / 01-2020
Technical Data 8
3 
3.1 Ordering information
Equipment Versions
Order number
Description
Power supply
Cable length
8349.01-010
 EU Basic
230 VAC ±10%
10 m
8349.11-010
 EU + DSL Modem
230 VAC ±10%
10 m
8349.11-003
 EU + DSL Modem
230 VAC ±10%
3 m
8349.21-010
 EU + Battery Backup
230 VAC ±10%
10 m
8349.31-010
 EU + DSL Modem + Battery Backup
230 VAC ±10%
10 m
8349.02-010
 US Basic
115 VAC ±10%
10 m
8349.12-010
 US + DSL Modem
115 VAC ±10%
10 m
8349.22-010
 US + Battery Backup
115 VAC ±10%
10 m
8349.32-010
 US + DSL Modem + Battery Backup
115 VAC ±10%
10 m
Table 1 Equipment versions.
Composition of order numbers:
8349.xx-yyy
8349 =  basic unit (instrument, documentation, transport box)
xx = Special interface, other features (modem, battery backup, etc.)
xx= Country code (EU or US)
yyy = Cable length (003 = 3m; 010 = 10 m; 050 = 50m)
3.2 Technical data
Measurement parameters
Measuring range
0 0 
Cloud detection range
26246 ft)
Resolution (measured)
5 m
NetCDF data resolution (*)
5 m 30 m in 5 m steps (can be set by the user)
15 m (default setting)
NetCDF high resolution data
5 m (defined for limited HR vector of data)
Logging time and reporting
cycle (*)
2 s to 600 s (programmable)
Default value: 15 s
Measurement objects
Aerosols, clouds (droplets, ice crystals)
Measured / set parameters
Backscatter raw data
Cloud heights up to 9 layers including penetration depth, max.
detectable range (MXD), vertical visibility (VOR), Sky Condition
Index (SCI), cloud cover (TCC, BCC), ...
Measuring principle
Lidar (optical, time of flight)
Optical parameters
Light source
Laser diode
Wavelength
905 nm
Pulse energy

Pulse repetition rate
8 kHz
Filter bandwidth
25 nm
Field-of-view receiver (FOV)
1.1 mrad
Extended NOHD
400 m (for 50 mm aperture)

 R1.7 / 01-2020
Technical Data 9
Data interfaces
Standard interfaces
RS485 half-duplex (ASCII); LAN (http, (S-)FTP, NetTools)
Optional interfaces
DSL, RS485 full-duplex (4 wire)
Electrical parameters
Power supply
230 VAC ±10 % or 115 VAC ±10 %
Line frequency
50 Hz, 60 Hz
Power consumption
Max 450 VA with activated case heater (default);
Max 300 VA without activated case heater
Power consumption in W
(depends on supply voltage)
Measuring unit heater: 250 W @115 / 230 VAC
Case heater: 150 W @115/ 230 VAC
UPS functionality (optional)
Internal backup battery for the electronics (> 1 hour)
Equipment safety
General safety
IEC 61010-1:2010 + A1
Laser Protection Class
1M according to IEC 60825-1:2014; complies with 21 CFR 1040.10
Protection housing
IEC/ EN 60529: IP 65; IEC/EN 61010-1: IK06 (1 Joule)
Protection electrical safety
Protection class I (protective earth needed)
Overvoltage Category
II
Pollution degree in IP65
housing
2
EMC
EN 61326 Class B (industrial use)
Conformity
CE
Operating conditions
Temperature range
-40 °C to +60 °C
Relative humidity
0% 100%
Wind
60 m/s
Maximum operating altitude
5000 m
Dimensions
Enclosure dimensions
(footprint x height)
W x H x L = 0.5 m x 0.5 m x 1.55 m
Packaging dimensions
W x H x L = 0.75 m x 0.86 m x 1.80 m
Weight
Weight
70 kg (complete system)
9.5 kg (measuring unit heaviest replacement part)
Installation requirements
Suitable low-voltage
distribution systems
TN-
neutral and protective conductor separate
TN-C 
conductor combined in one conductor
Connection type
Fixed connection, grounding by means of ground connection clamp
(see Figure 12)
Resources to be provided by the operator
Lightning protection
- Internal lightning protection is provided
- External lightning protection must be provided
Grounding
Grounding system according to DIN V VDE 0185-3
Requirements for installation
- Isolation device for disconnection from low-voltage network in

- Easily accessible
- 
- Pre-fuse only needed for 230 VAC variant: 10 A gG time-lag
Table 2 Technical data.

 R1.7 / 01-2020
Technical Data 10
(*) the combination of high temporal and range resolution over the full range is limited due to file size and
processing time. Any combination of > 70MB daily NetCDF fle sizes is not supported by Lufft.
Example (standard operation mode): 15 m range resolution over 10 km range with 15 s time resolution
results in 17 MB daily NetCDF file sizes.