SOMMER SPA User manual

SPA

Snow Pack Analyzer

Document version: 2012-Jan

Software version: 3.33

User Manual

ommer

easurement System

echnology.

User Manual SPA Snow Pack Analyser

Contents

GENERAL INFORMATION...................................................................................................................................... 1

1.1.

RINCIPLE OF MEASUREMENT

..............................................................................................................................1

1.2.

EASUREMENT PARAMETERS

..............................................................................................................................2

HARDWARE............................................................................................................................................................... 3

2.1.

SPA-

SENSORS

.....................................................................................................................................................3

2.2.

ORRECTION LENGTH SENSOR

(

POTENTIOMETER

).............................................................................................3

2.3.

NOW DEPTH SENSOR

..........................................................................................................................................3

2.4.

ONTROL UNIT

IASP............................................................................................................................................3

2.5.

RAMEWORK

.........................................................................................................................................................4

INSTALLATION.........................................................................................................................................................5

3.1.

EASUREMENT SITE

.............................................................................................................................................5

3.2.

RAMEWORK

.........................................................................................................................................................5

3.3.

NOW DEPTH SENSOR

..........................................................................................................................................5

3.4.

LOPING

SPA-

SENSOR

........................................................................................................................................6

3.5.

ORRECTION LENGTH SENSOR

............................................................................................................................8

3.6.

ORIZONTAL

SPA-

SENSORS

................................................................................................................................9

3.7.

OUSING

.............................................................................................................................................................10

3.8.

OWER SUPPLY

..................................................................................................................................................10

3.9.

UMMARY

............................................................................................................................................................10

PARAMETERIZATION...........................................................................................................................................11

4.1.

ONNECTION ESTABLISHMENT VIA TERMINAL

....................................................................................................11

4.1.1.

Local communication...............................................................................................................................11

4.1.2.

Connection affirmation............................................................................................................................. 11

4.2.

AIN

ENU

.........................................................................................................................................................12

NECESSARY PARAMETER ADJUSTMENTS AFTER ASSEMBLY.............................................................13

5.1.

NOW DEPTH

......................................................................................................................................................13

5.2.

ISPLACEMENT OFFSET

ENGTH CORRECTION

...............................................................................................13

5.3.

EOMETRIC PARAMETERS

..................................................................................................................................14

5.4.

CTUAL

NOW DEPTH

........................................................................................................................................15

5.5.

EASUREMENT INTERVAL

...................................................................................................................................15

DESCRIPTION OF THE PARAMETERS.............................................................................................................17

DATA OUTPUT........................................................................................................................................................27

7.1.

ROTOCOL VALUES

.............................................................................................................................................27

7.2.

MIO

ROTOCOL

..................................................................................................................................................29

7.3.

TANDARD PROTOCOL

........................................................................................................................................31

SUPPORT.................................................................................................................................................................32

BASE SETTINGS AND DEFAULT VALUES......................................................................................................33

10.

TECHNICAL DATA.............................................................................................................................................35

User Manual SPA Snow Pack Analyser

Safety Information

Please read this entire manual before setting up or operating this equipment. The non-compliance of this

manual could result in damage to the equipment. Also in the case of non-compliance injuries of individuals

cannot be excluded totally.

To make sure that the protection provided of and by this equipment is not impaired, do not use or install

this equipment in any manner other than that specified in this manual.

User Manual SPA Snow Pack Analyser

- 1 -

1.General information

Snow has an enormous variability in space and time. Up to now mainly punctual measurements are

available for the relevant parameters. The Snow Pack Analysing System (SPA) constitutes an innovation

in snow measurement. It is a system for automatic and continuous measurement of all relevant snow

parameters like snow depth, snow density, snow water equivalent and contents of liquid water and ice.

There are several possibilities to install the system, depending on demand.

1.1. Principle of measurement

Fig. 1: Principle of measurement of the SPA-sensor

Snow consists of the three components ice, water and air. Referring to different measurement

frequencies, these components show different dielectric constants. Measuring the complex impedance

along a flat ribbon sensor (SPA-sensor) with at least two frequencies allows to estimate the volume

contents of the individual components. These specific volume contents equate the liquid water, ice and air

in the snow pack, which result in the snow density and the snow water equivalent.

User Manual SPA Snow Pack Analyser

- 2 -

1.2. Measurement parameters

Snow density

The SPA calculates the snow density of the snow surrounding the SPA-sensor.

Snow water equivalent SWE

The SWE corresponds to the water column in mm resulting from the melting of the complete snow cover

on a defined area. It is calculated from the snow density of sloping sensors with respect to the snow

depth.

Contents of liquid water and ice in snow pack

The volumetric contents of ice and liquid water in the snow are output in %.

Snow depth

The snow depth is measured by an ultra sonic sensor. It is necessary to determine the SWE.

User Manual SPA Snow Pack Analyser

- 3 -

2.Hardware

Fig. 2: SPA-sensor

Fig. 3: IASP control unit

2.1. SPA-sensors

The SPA-sensor is a 6 cm wide flat ribbon sensor including three copper wires. The length varies between

3 and 10 m. Its ends are terminated by boxes including mounting rings. The connection cable is led out of

one box.

2.2. Correction length sensor (potentiometer)

The deforming of sloping sensors due to the snow pack can be corrected by measuring the additional

length of the sensor rope at the suspension. The sensor measures the rotation of the suspension roll and

converts the values into length. The correction is automatically included in the calculation.

2.3. Snow depth sensor

The snow depth sensor USH-8 is based on transit-time measurements of an ultrasonic pulse between the

sensor and the snow surface. It is mounted with an extension arm on a mast and is directly connected to

the control unit.

The snow depth is an essential parameter to calculate the snow pack parameters of sloping sensors. On

one hand the length of the sensor in snow is determined and on the other hand the total SWE is

calculated using the actual snow depth.

2.4. Control unit IASP

The control unit IASP performs all measurements, switches between sensors and calculates the snow

parameters with respect to snow depth, length correction and geometric parameters. The data is output

via a RS-232 interface.

The analogue input F2-1 (#1) is preadjusted for the length correction. The analogue input F3-3 (#6) is

preadjusted for the USH-8 snow depth sensor.

User Manual SPA Snow Pack Analyser

- 4 -

Tab. 1: Connector assignment for Fig. 3;

the analogue input F3-3 (#6) is reserved for the USH-8 snow depth sensor

2.5. Framework

The framework enables the installation of one sloping and up to three horizontal sensors and secures a

tight and upright positioning of the sensors. It includes the basement framework, a mast for the installation

of the sloping sensor, the snow depth sensor and the housing and suspension equipment for the SPA

sensors consisting of springs, levers and stretching devices.

User Manual SPA Snow Pack Analyser

- 5 -

3.Installation

3.1. Measurement site

A representative measurement site is horizontal and is not located in a basin or on a ridge. It is free of

influences from trees or rocks and is not exposed to intensive winds. An undisturbed accumulation of the

snow pack has to be guaranteed.

3.2. Framework

Fig. 4: SPA framework Fig. 5: Connection construction with foot

First the basement framework is placed on the ground. It is delivered separated in two parts each with

about two 3 m long beams connected with cross-beams. The side with the two round cross-beams is for

the installation of the mast and the fixation of the suspension, the side with the rectangle cross-beam is

used for fixing the sensors. The inner L-shaped cross-beam can be located at three position, depending

on the installation height of the sloping sensor of 1.5, 2 or 2.5 m.

The two parts of the framework are connected with a connection construction consisting of a u-profile,

screws and a foot. It is important to install the framework with an initial tension to resist the forces of the

spanned sensors. This is achieved by connecting the two parts of the framework in a small angle, support

it with the foot and fix it with the screws. The height of the foot should be at least 10 cm.

After the installation of the basement the mast is installed on the inner cross-beam. The mast holds the

snow depth sensor, the rolls for the sloping SPA-sensor and the housing for the measurement and

communication devices. It is recommended to install the snow depth sensor before erecting the mast. The

mast is supported with two steel wires to be spanned to the near edges of the basement.

3.3. Snow depth sensor

The snow sensor is an ultra sonic sensors using transit time measurement. It is installed on the top of the

mast using the extension arm. The installation height has to be 1 m above the expected maximal snow

depth. The extension arm should be orientated on one side of the framework to guarantee a snow

measurement free of influences. Ensure that the area of the snow depth measurement is free of

constructions, sensors or cables and that it will be undisturbed during the complete winter season. Use

barrier tapes to prevent accidental entering of the area.

User Manual SPA Snow Pack Analyser

- 6 -

3.4. Sloping SPA-sensor

At the skew SPA the bend of the sensor which is also with strong tension not preventable at snow cover

has to be considered.

Without snow cover the sensor

has, caused by the tension, a

straight course.

Fig. 6: Sketch of the sloping sensor, the

tensioner part differs for simplicity from reality

With snow cover it is

possible that the

sensor has at the air /

snow boun-dary a

slight bend.

The sensor is not

stretchable but

nevertheless the bend

leads to an extension

of the fractional part of

the sensor which is

covered by snow.

This increase can be

determined over the

length change in the

sensor brace length.

Fig. 7: Sketch of the sloping band with a snow cover; the slight

bend in the sensor is best noticeable at the symmetry

lines

User Manual SPA Snow Pack Analyser

- 7 -

Fig. 8: Upper end of the sloping sensor with the upper part of the tensioner; consider that

the potentiometer is not included at every SPA

Attention: The inner and outer roll rotate at a length displacement with different extent.

The rotation is only measured at the outer roll. So it is very important that the

ropes are not interchanged during the assembling.

Fig. 9: Upper end of the sloping sensor with the upper part of the tensioner from different

views

Table of contents

Other SOMMER Measuring Instrument manuals

SOMMER

SOMMER RQ-30 ADMS User manual

SOMMER

SOMMER SMA-2 User manual

SOMMER

SOMMER RG-30 User manual

SOMMER

SOMMER RL-15 User manual

SOMMER

SOMMER SPA-2 User manual

SOMMER

SOMMER TQ-S Tracer User manual

Popular Measuring Instrument manuals by other brands

Suaoki

Suaoki D40 user manual

Elster

Elster BK-G1.6 operating instructions

Endress+Hauser

Endress+Hauser Deltabar FMD71 technical information

Duratool

Duratool D03128 manual

Vega

Vega VEGAPULS 65 Quick setup guide

Tonghui

Tonghui TH2618B Operation manual

Tenmars

Tenmars TM-801 user manual

MSR

MSR 145 user manual

TPS

TPS WP-82 manual

ELMETRON

ELMETRON CP-511 user manual

PCB Piezotronics

PCB Piezotronics 003C30 Installation and operating manual

Tenma

Tenma 72-10465 manual

Endress+Hauser

Endress+Hauser Proline Promag 50 Brief operating instructions

Siemens

Siemens SITRANS F Coriolis FCT030 Function manual

KLINGER

KLINGER CMF V Series instruction manual

EXFO

EXFO FTB-2 Notice

Keysight

Keysight M8290A Getting started guide

ADTEK

ADTEK MW-5 operating manual