Level Indicator | Automatic
Tank Gauges | Radar
Gauge | NT 5000 Systems
2800i High Accuracy
Servo Tank Gauge
Control Systems 2800i High Accuracy Servo Tank Gauge is designed
specifically for use in Custody Transfer and Inventory Management
applications across the full range of modern storage tank designs.
2800i measures product level, water interface and product density
in a single micro-processor based unit.
the gauge to one of the Motherwell Control Systems range of MCS
3780 Series temperature probes provides measurement of both product
and vapour temperature.
product level measurement – accurate to ±1mm.
referencing – the gauge can be commanded to self check by
returning to the tank top reference point.
referencing – measures sediment accumulation and/or tank
filtering eliminates the effect of ripples to give continuous
true level measurement.
to four level alarm contacts.
measurement – accurate to ±0.1 ºC
Single Spot, Multiple Spot or averaging Temperature Probes
elements of Multiple and Averaging Probes are read continuously.
profiling illustrates thermal product stratification and
provides vapour temperature measurement.
Interface and Density Measurement
Interface measurement – accurate to ±2mm.
profiling illustrates product stratification
Control Systems 2800i measures liquid level based on the principle
of liquid displacement. A displacer is suspended on a stainless
steel wire payed out from a grooved drum housed in the gauge enclosure.
A highly sensitive
torque measurement device continuously measures the effective weight
of the displacer which, under steady state level conditions, is
half immersed in the liquid. Should the level change, the displacer
undergoes an apparent change of weight. The gauge microprocessor
senses this change in weight and causes a servo motor to rotate
the measuring drum until balance is restored.
determined by measuring the effective weight of the displacer when
completely immersed. Sample readings, recorded at configurable intervals
as the displacer travels down through the liquid, provide density
level and tank base measurement are achieved by recording the point
at which the gauge recognises the effective displacer weight in
water and at the tank base respectively.
Benefits of Motherwell Control Systems 2800i Servo Gauge :
Safe (Eex ia IIB T4) with the added benefit of no electronics
exposed to the tank atmosphere.
power requirements enable both power and communications
to be safely distributed via one 4-wire cable running around
the tank farm.
Visibility large Liquid Crystal Display provides selectable
Level, Temperature, Interface or Density readings at all
display for mounting at tank base.
memory: 2800I will restore itself to full operation in the
event of a power loss.
across a wide range of process and environmental conditions.
of installation options to suit all tanks, including high
pressure applications; and a flexible coupling installation
for tanks with undefined deformation characteristics.
control by single push-button: user friendly.
control and monitoring via industry standard multi-dropped
serial communications, including extensive diagnostic information.
Protection through galvanic isolation.
track record – proven in a wide variety of applications.
have asked the question WHY is 2800I certified Intrinsically Safe
when all other Tank Gauge manufacturers have chosen Explosion Proof
The answer is
quite simple. Whilst Intrinsic Safety requires specialist skills
in design, there are tremendous benefits to be gained in terms of
operation and maintenance.
operational safety –
‘PREVENTION RATHER THAN CURE TECHNOLOGY’ means that the gauge
is safe in all circumstances, even when the integrity of the
electronic enclosure is compromised.
reliability – the electronic components are operating
at extremely low current levels and consequently 2800I is
considerably less prone to component failure than non-IS circuitry.
Points for Consideration
electronics are certified for use in Zone O (inside the tank).
2800I electronics are not however, exposed to the tank atmosphere
– the drum enclosure is magnetically coupled to the enclosure
containing the motor and electronics.
therefore far exceeds the requirements of hazardous area approvals.
is certified Ex ia IIB T4.
occasionally ask how 2800I has been certified IS when the
current quoted on the gauge display label reads what might,
in instrument terms, be considered a high figure at 276mA.
lies in the criteria utilised for approval. The test report
from the UK Health & Safety Executive, BASEEFA, discusses
the input / output parameters of each section of the gauge.
As you can see, the current is only one parameter considered
when granting IS certification – the voltage, power, current
and particularly the capacitance and inductance of the unit
are all used together in assessing the IS rating – which revolves
around energy storage. 2800I has extremely low capacitance
and inductance and is simply incapable of causing ignition
in the IIB T4 environment.
– 2800I can be maintained in service. IS certification means that
the electronics can be worked upon to allow verification and fault
finding whilst installed on the tank. Eliminating the costly and
time-consuming task of removing the gauge, to a safe working area
for service and testing. A tremendous advantage over explosion proof
equipment where the fault conditions may ‘disappear’ in the workshop
of the MCS Servo Gauge as you will appreciate can give a significant
reduction to the gauge “Out of commission” time, during the period
of service. It will also reduce the required level of servicing
manpower. Since the removal and transportation of the gauge from
the storage tank is no longer a requirement, the task can now be
easily accomplished by one Service Engineer.
Then, in addition
to operational safety offered by the MCS Servo Gauge, the risk of
danger to servicing personnel is reduced by it’s “Intrinsic safety,”
permitting improved and much safer working practices at the tank
top. In fact the intrinsic safety of the gauge not only diminishes
potential risk of damage to personnel but also the equipment.
With an MCS
2800i Servo Tank Level Gauge, installation to the storage tank is
a one off event at the time of initial installation and commissioning.
Further, with its proven track record of service and reliability,
it is by far the best solution to our client’s level gauging requirements.