Armfield S12-MKII User manual

Advanced Environmental
Hydrology System
Instruction Manual
S12-MKII
ISSUE 21
February 2014

ii
Table of Contents
Copyright and Trademarks...................................................................................... 1
General Overview ....................................................................................................... 2
Equipment Diagrams................................................................................................... 4
Important Safety Information....................................................................................... 7
Introduction.............................................................................................................. 7
Electrical Safety....................................................................................................... 7
Heavy Equipment.................................................................................................... 7
Water Borne Hazards.............................................................................................. 7
The COSHH Regulations ........................................................................................ 8
Description................................................................................................................ 10
Overview................................................................................................................ 10
Frame.................................................................................................................... 10
Water Feeds.......................................................................................................... 10
Sand Tank............................................................................................................. 11
Outlet Collecting Tank........................................................................................... 12
S12-MKII-50 (S12-MKII Including Data Logging and Educational Software)........ 12
Overhead Spray Nozzles....................................................................................... 13
River Inlet Tank ..................................................................................................... 13
Choice of Granular Material for the Sand Tank..................................................... 14
Accessories........................................................................................................... 14
Installation................................................................................................................. 16
Advisory................................................................................................................. 16
Electrical Supply.................................................................................................... 16
Cold Water Supply................................................................................................. 17
Laboratory Drain.................................................................................................... 17
Installing the PC Software (Version S12-MKII-50 only)......................................... 17
Installing the Equipment........................................................................................ 18
Commissioning...................................................................................................... 19
Electrical Wiring Diagram...................................................................................... 21

Table of Contents
iii
Operation .................................................................................................................. 22
Operating the PC Software.................................................................................... 22
Operating the Equipment....................................................................................... 24
Equipment Specifications.......................................................................................... 25
Equipment Location............................................................................................... 25
Electromagnetic Compatibility............................................................................... 25
Environmental Conditions...................................................................................... 25
Routine Maintenance................................................................................................ 26
Responsibility ........................................................................................................ 26
General.................................................................................................................. 26
Load Sensor.......................................................................................................... 28
Laboratory Teaching Exercises................................................................................. 29
Index to Exercises................................................................................................. 29
General Equations and Constants......................................................................... 29
Exercise A - Rainfall-runoff relationships (storm hydrographs)................................. 32
Exercise B - Generation of overland flow.................................................................. 37
Exercise C - Initiation and characteristics of bedload motion.................................... 39
Exercise D - Effect of changing stream power on channel morphology.................... 42
Exercise E - Effect of base level change................................................................... 45
Exercise F - Scour in open channel flow................................................................... 47
Exercise G - Water abstraction from a well in a confined aquifer ............................. 49
Exercise H - Water abstraction from a well in an unconfined aquifer........................ 53
Exercise I - Water abstraction from a number of neighbouring wells........................ 56
Exercise J - Rainfall on a circular island with a central well...................................... 59
Exercise K - Ground water flow between two canals with and without rainfall.......... 61
Contact Details for Further Information..................................................................... 63

1
Disclaimer
This document and all the information contained within it is proprietary to Armfield
Limited. This document must not be used for any purpose other than that for which it
is supplied and its contents must not be reproduced, modified, adapted, published,
translated or disclosed to any third party, in whole or in part, without the prior written
permission of Armfield Limited.
Should you have any queries or comments, please contact the Armfield Customer
Support helpdesk (Monday to Thursday: 0830 - 1730 and Friday: 0830 - 1300 UK
time). Contact details are as follows:
United Kingdom International
(0) 1425 478781
(calls charged at local rate) [phone] (international rates apply)
Email: [email protected]
Fax: [phone]
Copyright and Trademarks
Copyright © 2014 Armfield Limited. All rights reserved.
Any technical documentation made available by Armfield Limited is the copyright
work of Armfield Limited and wholly owned by Armfield Limited.
Brands and product names mentioned in this manual may be trademarks or
registered trademarks of their respective companies and are hereby acknowledged.

2
General Overview
This floor-standing unit is the only Hydrology System that includes features making it
suitable for studying fluvial geomorphology. It combines the capabilities of the S10
Rainfall Hydrographs and S11 Ground Water Flow Unit into a single comprehensive
facility. The system is fully instrumented for investigation of rainfall/run-off
hydrographs, ground water abstraction studies and unique to this apparatus, fluvial
mechanics.
This apparatus sets out to demonstrate, on a small scale, some of the physical
processes found in hydrology. These processes fall into two related categories: the
relationship between rainfall and run-off from catchment areas of varying permeability
and the abstraction of ground water by wells, both with and without surface recharge
from rainfall.
Thus it can be seen that it is concerned with that part of the hydrological cycle
bounded by the arrival of "net rainfall" on the ground surface and catchment run-off
either by surface streams or well abstraction.
The hydrological cycle describes the complete movement of water between the
atmosphere, the land surfaces and the water masses of the earth. There are a
number of possible routes that water can follow in moving round this cycle and these
are outlined below.
Precipitation (rainfall) on the land surfaces is disposed of in various ways. What
water remains after the ground has been wetted and evaporation and transpiration
losses have been deducted, is termed the "net rainfall" and this may
i. soak into the ground (infiltrate) to join the ground water held in voids (normally
very small)
ii. fill up surface depressions to form puddles, or
iii. any remaining will flow over the ground surface in the downhill direction to
form streams and, subsequently, rivers.
Ground water also flows laterally under the influence of slopes, to reappear at the
surface either to form springs or to increase stream flow by reverse infiltration
through the bed.

General Overview
3
Abstraction from wells is another way in which water can leave a catchment area and
it can, therefore, be thought of as forming part of the run-off.
A proper understanding of these processes and their inter-relationships is essential
for many purposes. Engineers are commonly concerned with the provision of water
supplies for urban and irrigation needs; with the estimation of flood magnitudes and
frequencies; with the consequences of land drainage works on flood risks, on the use
of wells to de-water construction excavations and the drainage of lakes and polders.
Geologists and geographers are frequently faced with problems which involve
hydrological processes such as drawing up a water balance for a catchment area,
the investigation of morphological processes in rivers and streams, and the control of
mud flows and soil erosion caused by surface and sub-surface water flows.
The range of experimental capabilities is significantly increased by the provision of a
river inlet tank and outlet collecting tank. These enable a range of fluvial mechanics
experiments to be carried out in related topics such as river flow and sediment
transport, initiation and characteristics of bed-load motion, general and local scour in
open channel flow etc.

4
Equipment Diagrams
Figure 1: Front View of S12-MKII Hydrology System

Equipment Diagrams
5
Figure 2: Plan View of S12-MKII Hydrology System

Armfield Instruction Manual
6
Figure 3: End View of S12-MKII Hydrology System

7
Important Safety Information
Introduction
All practical work areas and laboratories should be covered by local safety
regulations which must be followed at all times.
It is the responsibility of the owner to ensure that all users are made aware of
relevant local regulations, and that the apparatus is operated in accordance with
those regulations. If requested then Armfield can supply a typical set of standard
laboratory safety rules, but these are guidelines only and should be modified as
required. Supervision of users should be provided whenever appropriate.
Your S12-MKII Hydrology System has been designed to be safe in use when
installed, operated and maintained in accordance with the instructions in this manual.
As with any piece of sophisticated equipment, dangers exist if the equipment is
misused, mishandled or badly maintained.
Electrical Safety
There is a potential hazard of injury from electric shock due to mains electrical supply
to water pump and Data Logging accessory when fitted (included on version S12-
MKII-50).
To give increased operator protection, the unit incorporates a Residual Current
Device (RCD), alternatively called an Earth Leakage Circuit Breaker, as an integral
part of this equipment. If through misuse or accident the equipment becomes
electrically dangerous, the RCD will switch off the electrical supply and reduce the
severity of any electric shock received by an operator to a level which, under normal
circumstances, will not cause injury to that person.
At least once each month, check that the RCD is operating correctly by pressing the
TEST button. The circuit breaker MUST trip when the button is pressed. Failure to
trip means that the operator is not protected and the equipment must be checked and
repaired by a competent electrician before it is used.
Heavy Equipment
There is a potential hazard of injury from incorrect handing.
The equipment is heavy and must be handled properly when unpacking and
positioning. Sand tank is heavy when filled with sand or water and care must be
exercised when using the jacking system.
Water Borne Hazards
The equipment described in this instruction manual involves the use of water, which
under certain conditions can create a health hazard due to infection by harmful
micro-organisms.
For example, the microscopic bacterium called Legionella pneumophila will feed on
any scale, rust, algae or sludge in water and will breed rapidly if the temperature of
water is between 20 and 45°C. Any water containing this bacterium which is sprayed
or splashed creating air-borne droplets can produce a form of pneumonia called
Legionnaires Disease which is potentially fatal.
Legionella is not the only harmful micro-organism which can infect water, but it
serves as a useful example of the need for cleanliness.

Armfield Instruction Manual
8
Under the COSHH regulations, the following precautions must be observed:
Any water contained within the product must not be allowed to stagnate, ie.
the water must be changed regularly.
Any rust, sludge, scale or algae on which micro-organisms can feed must be
removed regularly, i.e. the equipment must be cleaned regularly.
Where practicable the water should be maintained at a temperature below
20°C. If this is not practicable then the water should be disinfected if it is safe
and appropriate to do so. Note that other hazards may exist in the handling of
biocides used to disinfect the water.
A scheme should be prepared for preventing or controlling the risk
incorporating all of the actions listed above.
Further details on preventing infection are contained in the publication “The Control
of Legionellosis including Legionnaires Disease” - Health and Safety Series booklet
HS (G) 70.
Note: Water will stagnate if left in any of the tanks. Water must be changed at regular
intervals. Overhead spray system and sand in the tank must be flushed at regular
intervals to exclude micro-organisms.
The COSHH Regulations
The Control of Substances Hazardous to Health Regulations (1988)
The COSHH regulations impose a duty on employers to protect employees and
others from substances used at work, which may be hazardous to health. The
regulations require you to make an assessment of all operations, which are liable to
expose any person to hazardous solids, liquids, dusts, vapours, gases or micro-
organisms. You are also required to introduce suitable procedures for handling these
substances and keep appropriate records.
Since the equipment supplied by Armfield Limited may involve the use of substances
which can be hazardous (for example, cleaning fluids used for maintenance or
chemicals used for particular demonstrations) it is essential that the laboratory
supervisor or some other person in authority is responsible for implementing the
COSHH regulations.
Parts of the above regulations are to ensure that the relevant Health and Safety Data
Sheets are available for all hazardous substances used in the laboratory. Any person
using a hazardous substance must be informed of the following:
Physical data about the substance.
Any hazard from fire or explosion.
Any hazard to health.
Appropriate First Aid treatment.
Any hazard from reaction with other substances.
How to clean/dispose of spillage.

Important Safety Information
9
Appropriate protective measures.
Appropriate storage and handling.
Although these regulations may not be applicable in your country, it is strongly
recommended that a similar approach be adopted for the protection of the students
operating the equipment. Local regulations must also be considered.

10
Description
Where necessary, refer to the drawings in the Equipment Diagrams section.
Overview
The equipment consists of a sand tank (21) that is mounted on a support frame (1)
with the necessary services, features and instrumentation to facilitate studies of
ground water flow, ground water abstraction, flood hydrographs and fluvial
mechanics.
Frame
The frame incorporates an adjustable foot (3) on each leg to allow the equipment to
be levelled. It is suggested that the top edge of the sand tank (21) be used as the
datum when levelling the equipment.
The frame incorporates a pair of scissor type jacks (34) at one end that allow the
sand tank to be elevated. The jacks are linked so that the sand tank remains stable
when raising or lowering. An indicator (36) shows the gradient of the sand tank. The
jacking handle is simply inserted into the coupling (35) on the front jack and rotated
clockwise to raise the sand tank or anticlockwise to lower the sand tank. The jacking
handle should be removed after adjusting the elevation of the sand tank.
CAUTION: Although the sand tank cannot move suddenly when adjusting the
elevation, extreme care should be taken when operating the jacks to prevent
crushing of fingers, hands or other objects between the upper and lower frames.
Water Feeds
A sump tank (4) and centrifugal pump (10) mounted in the frame, beneath the sand
tank, provide the water for the various demonstrations. Water exiting the sand tank
from the various outlets returns to the sump tank under gravity for reuse. An overflow
pipe (2) on the side of the side of the sump tank ensures that the tank cannot be
overfilled. A drain valve (6) is connected to a tapping at the base of the sump tank.
The centrifugal pump draws water from the sump tank via a tapping (9) at the base of
the tank. Water from the pump passes through two parallel feed arrangements, each
incorporating a filter (12), pressure regulator (11), feed flow control valve (13) and
variable area flowmeter (14). The pressure regulator in each feed ensures that the
flow is not affected by changes in the other feed provided that the regulator is
adjusted to suit. The outlet from each feed is terminated with a self-sealing quick-
release connector (15) that allows water to be fed to either end of the sand tank, the
spray nozzles or the river inlet tank as required via the appropriate flexible
connection. The self-sealing quick-release connectors allow rapid changes to the
configuration without the need for tools.
The outlet from the centrifugal pump incorporates a pressure relief valve to limit the
system pressure to a maximum of approximately 3.0 barg and prevent the pump from
overheating if the flow from the two outlets is restricted or stopped. Water discharging
from the relief valve is returned to the sump tank via a connection in the side wall of
the tank. When demand from the two outlets is high, the relief valve will remain
closed to maintain the pressure in the system. When demand is reduced and the
system pressure rises above 3.0 barg, the valve will open to relieve the excess flow.
The relief pressure is adjustable and set prior to delivery but instructions are included
in the Routine Maintenance section of this manual should further adjustment be
necessary.

Description
11
The electrical control box is mounted on the frame below the sand tank and
incorporates a starter (7) for the pump and an RCD (8) to protect the operator against
electrical shock.
Sand Tank
The shallow sand tank (21) is fabricated from stainless steel for corrosion resistance
and should be filled with sand (not supplied by Armfield) or other granular material as
appropriate to the studies (refer to page 15 for details on choosing a suitable granular
material). An array of tapping points (37) in the sand tank floor is connected to a
multi-tube manometer (20) that enables the water table surface (phreatic surface) to
be determined. The level in each tube can be read by sliding the common scale
along the track at the top of the manometer. Before using the manometer to measure
water levels it is important to expel air from the flexible tubes connecting the
manometer tubes to the tapping points. (Refer to the Commissioning section). Each
tapping (37) in the sand tank floor incorporates a filter mesh to retain the sand while
allowing the water to flow. Two cylindrical wells (19) are also included in the sand
tank floor. The wells are covered with stainless steel mesh to prevent the loss of
sand. Valves and pipework beneath the sand tank allow the water draining from each
well to return to the sump tank. In-line feed flow control valves (32) allow the flow to
be varied. Flexible outlet hoses (33) allow the water to be diverted to a collecting
vessel (not supplied) for the purpose of measuring the volumetric flowrate. The two
wells are purposely designed to be short in length so that they can be left in position
without affecting the surface flow experiments. The plug of sand directly above each
well can be removed if required for abstraction experiments but the affect on the
results will be negligible if the sand is left in place.
The reference number/spacing of the tappings (37) and the position of the wells (19)
is shown below:
Location of tappings and wells in the sand tank
A perforated pipe (22), in the form of a French drain, is buried in the sand at each
end of the sand tank. These allow water to be drained from the sand tank or admitted
to the sand tank as required. Each French drain is connected through the side wall of
the sand tank to a flexible tube terminated with a self-sealing quick-release

Armfield Instruction Manual
12
connector. When it is required to drain water from the sand tank the flexible tube is
connected to one of the quick-release connectors (5) on the side of the sump tank,
allowing the water to return to the sump tank. The flow of water can be varied using
the in-line valves (32). When it is required to admit water to the sand tank the flexible
tube is connected to one of the water feeds via the quick-release connector (15).
A deep cut-out (31) at the left-hand end of the sand tank allows water (and
transported sediment) to leave the sand tank. This cut-out incorporates side slots that
locate stop-logs (rectangular strips of plastic) that create a rectangular weir. Adding
or subtracting stop-logs of different sizes can vary the height of the weir. A weir
chute/diffuser (26), fabricated from clear acrylic, is bolted to the end wall of the sand
tank adjacent to the cut-out. The weir chute/diffuser allows the water and sand exiting
the sand tank to fall into the outlet collecting tank (28) with minimal disturbance to the
surface of the water or any collected sediment in the outlet collecting tank (described
below). A clear polythene skirt with slits is attached to the bottom of the weir
chute/diffuser, using a rubber band, to minimise splashing as the water and sand fall
into the collecting tank.
Outlet Collecting Tank
Water and sediment exiting the sand tank via the weir chute/diffuser is deposited into
the outlet collecting tank (28) that is designed to measure the flow of water and
collect any sediment washed from the sand tank. This tank is fabricated from clear
acrylic and incorporates the following features:
The water and sediment fall into the open area of the tank. A vertical mesh screen
(30), supported by perforated plates on either side, ensures that sediment is retained
in the tank. The water flows through the mesh, along a stilling channel then over a
narrow rectangular notch (31) before discharging into a funnel (29) that returns the
water to the sump tank for re-use. The flowrate of the water is determined from the
height of the water upstream of the notch using an inclined manometer that
incorporates a scale calibrated directly in litres/min. The manometer is mounted
directly on the side of the outlet collecting tank.
Sediment falling into the tank is deposited in the bottom of the tank. The sand can be
removed by lifting the tank clear from its support. If it is required to collect the sand
for quantitative measurements then a piece of fine cloth or a small strainer can be
positioned beneath the weir chute/diffuser to collect the sediment. If this is changed
at regular intervals then the rate of accumulation of the sediment can be determined.
When version S12-MKII-50 has been supplied, additional instrumentation and a USB
interface is included that can be used to measure both the water flow and the
accumulation of sediment continuously using a PC.
S12-MKII-50 (S12-MKII Including Data Logging and Educational
Software)
Note: This option can only be supplied at the time of ordering the equipment and
cannot be fitted to en existing S12-MKII.
This system works by measuring the height of the water and the combined weight of
the sand and water collected in the outlet tank (28). The water flow rate is calculated
from the height over the outlet weir (27) and the sediment flow rate is calculated from
the rate of change of the weight. The system comes with educational software
incorporating help texts, graph plotting, etc. and requires a user provided PC with an

Description
13
available USB port. Refer to the sections Installing the Software and Operating the
Software for further information. Alternatively, refer to the Help text in the software.
The electronics associated with the load cell and pressure sensor are installed in an
enclosure that is mounted underneath the support for the Outlet Collecting Tank. The
load cell is located underneath the Outlet Collecting Tank and the pressure sensor is
connected to a tapping adjacent to the inclined manometer on the side of the Outlet
Collecting Tank. The lead from the pressure sensor can be disconnected from the
front of the electrical enclosure when it is required to remove the tank for emptying /
cleaning. After refilling the tank with water to the base of the weir it will be necessary
to re-prime the connection to the pressure sensor to eliminate any air bubbles.
Overhead Spray Nozzles
Rainfall onto the catchment area is provided by two rows of four spray nozzles (18)
above the tank, mounted on a support frame (24). The height of the spray nozzles
above the sand tank can be varied to optimise the demonstration by adjusting the
height of the support frame. This is achieved by withdrawing the spring-loaded
plunger (25) at each end, raising or lowering the support frame to the required height,
then re-locating the spring loaded plunger in the appropriate hole. One person at
each end of the equipment should hold the support frame while performing the
adjustment.
An isolating valve (19) upstream of each nozzle allows the pattern to be changed as
required. Since the flowrate through each nozzle is dependent on the pressure, if the
appropriate pressure regulator (12) is adjusted to give the required flowrate then the
flow through each nozzle will remain constant when other nozzles are turned on or
off. To achieve this the feed flow control valve (13) should be opened fully and the
pressure regulator adjusted to give the required flow through the nozzles.
The flexible tube from the arrangement of spray nozzles is connected to one of the
water feeds, when required, using the self-sealing quick release connector (15). The
height of the nozzles should be adjusted at the required flowrate to give adequate
coverage over the surface of the sand without excessive spray over the sides of the
sand tank as described above.
River Inlet Tank
A river inlet tank (17) mounted at the right-hand end of the sand tank allows a stream
of water to flow onto the surface of the sand, simulating the flow from a river
upstream. The river inlet tank is fabricated from stainless steel and is bolted to the
end wall of the sand tank adjacent to the shallow cut-out. Water enters at the base of
the tank, flows upwards through a bed of glass marbles (16) to minimise any
turbulence then flows sideways onto the surface of the sand through a rectangular
section.
An anti-erosion mat (small section of mesh) is supplied to reduce any local scour
where the water enters the sand tank. This mat is buried just beneath the surface of
the sand adjacent to the outlet of the river inlet tank.
The flexible tube from the base of the sand tank is connected to one of the water
feeds, when required, using the self-sealing quick release connector (15).

Armfield Instruction Manual
14
Choice of Granular Material for the Sand Tank
It has been found through experimentation that well-graded silica sand in the range
16/30 mesh (1000 micron to 500 micron) will allow all of the experiments described in
the teaching manual to be carried out without the need to change the sand between
runs. To minimise the cost of filling the tank it is suggested that 16/30 mesh
swimming pool silica filter grit be used. 550 kg of sand will be required to fill the tank.
Obviously the size and grading of the sand used in the catchment tank can be varied
to meet the particular needs of the experimenter. Fine sand will normally give a lower
coefficient of permeability and hence slower run-off and steeper water table slopes
than a coarse one.
Before loading any sand into the sand tank it is most important that the sand should
be first thoroughly washed to remove all silt and salts present. After filling with sand
it is suggested that the water is circulated via the French drains for a period of
approximately one hour then drained from the sump tank and re-filled with clean
water (See Commissioning section).
Note: It is important that the granular material used in the sand tank is free from fine
sediment as this will gradually block the filter material used on the French drains, the
two wells, the tappings to the manometer tubes and the filters in the pressure
regulators. The use of sand taken directly from a beach or quarry is not
recommended. If this is necessary then the sand must be given multiple washes with
intermediate drying on trays to eliminate the soluble salts etc. The sand should also
be graded using sieves to remove those fractions smaller than 500 microns and
larger than 1000 microns.
Accessories
The S12-MkII is supplied complete with the following accessories:
Tank Sealing Plate: Sometimes it is required to seal the end of the sand tank (e.g. for
groundwater flow demonstrations where leakage through the stop-log weir is
unacceptable). When this is the case, the rectangular plate supplied should be bolted
over the cut-out (31) in place of the weir chute/diffuser (26).
Scraper: When the sand tank has been filled with sand, the surface profile for the
various experiments can be formed using the scraper. One edge has square corners
to create sharp features and the other edge has rounded corners to prevent digging-
in or create softer features.
Sand Scoop: Having created the general surface profile using the scraper, any local
features or channels can be created using the small plastic scoop.
Anti-erosion Mat: This small section of mesh is buried just beneath the surface of the
sand adjacent to the outlet of the river inlet tank to reduce any local scour where the
water enters the sand tank.
S12-MODELS (Optional accessory): The range of experiments using this equipment
is endless and specific models can be fabricated by the user as required. However, a
set of basic models is available as on option to facilitate the various experiments
listed in the teaching manual. Refer to the Laboratory Teaching Exercises for details
on using the models. The following models are supplied with the S12-MODELS
option:

Description
15
a. Fabricated trays and rings:
Circular open ended ring, 500mm diameter x 60mm high
Small square open ended ring, 300mm x 300mm x 60mm high
Closed ring with removable central clear plastic standpipe, 500mm diameter x
60mm high
Large rectangular open ended ring, 1000mm x 500mm x 60mm high
Large rectangular closed ring with hole, 1000mm x 500mm x 60mm
b. Impermeable catchment:
1000 gauge Polythene sheet, sufficient to cover the catchment area.
c. Permeable catchment:
Sheets of absorbent material: sufficient to cover the catchment area.
d. Model structures machined from solid PVC:
Cylinder - 25mm diameter
Rectangular bridge pier - 25mm wide, 75mm long, 125mm high
Rounded bridge pier - As above but with semicircular ends
Streamlined bridge pier - As above but with ends chamfered (60oinc.)

16
Installation
Advisory
Before operating the equipment, it must be unpacked, assembled and installed as
described in the steps that follow. Safe use of the equipment depends on following
the correct installation procedure.
Where necessary, refer to the drawings in the Equipment Diagrams section.
Electrical Supply
S12-MKII-A or S12-MKII-50-A
The equipment requires connection to a single phase, fused electrical supply. The
standard electrical supply for this equipment is 230V, 50Hz. Check that the voltage
and frequency of the electrical supply agree with the label attached to the supply
cable on the equipment.
The equipment is supplied with an appropriate plug fitted so it will not be necessary
for an electrician to terminate any bare electrical connections when installing the
equipment. For information the supply cable and electrical wiring use the following
convention:
GREEN/YELLOW - EARTH
BROWN - LIVE (HOT)
BLUE - NEUTRAL
Supply fuse rating - 5 AMP
S12-MKII-B or S12-MKII-50-B
The equipment requires connection to a single phase, fused electrical supply. The
standard electrical supply for this equipment is 120V, 60Hz. Check that the voltage
and frequency of the electrical supply agree with the label attached to the supply
cable on the equipment.
Versions S12-MKII-B and S12-MKII-50-B are supplied with a loose transformer to
step-up the 120V supply to 230V to suit the equipment. The transformer should be
sited adjacent to the 120V mains outlet socket in the laboratory, in a dry location. The
mains lead from the S12-MKII or S12-MKII-50 is simply plugged into the 230V outlet
socket on the front of the transformer.
The equipment is supplied with appropriate plugs fitted so it will not be necessary for
an electrician to terminate any bare electrical connections when installing the
equipment. For information the supply cable and electrical wiring use the following
convention:
GREEN/YELLOW - EARTH
BROWN - LIVE (HOT)
BLUE - NEUTRAL
Supply fuse rating - 10 AMP