HERMetic Onecal - Honeywell Process Solutions

HERMetic Onecal
Digital thermometer with one reference point
for calibration.
HERMetic Onecal stands for one reference point only for
calibration. The reference point is the ice point which can easily
be reproduced. The calibration is done by simply pushing a
button. The characteristics of the RTD sensor are stored in the
memory of the instrument and are the same for any individual
sensor. Therefore a change of a sensor requires only an offset
calibration. Replacing the cable only does not require a new calibration because of the built-in
automatic cable compensation routine. The HERMetic Onecal is designed for use in hazardous
environments with outstanding characteristics regarding safety, ease of operation, accuracy,
reliability and cost efficient maintenance.
HERMetic Onecal: Intrinsically
safe portable digital thermometer
Up to 9 individual values can be stored in the memory. An automatic average
of the stored values can be achieved by entering the calculation menu. The
ergonomic and rugged design of the housing allows for an easy and safe
cable storage. The cable guides keeps the cable secured at all times. By
counting the number of cable loops the fed cable length can be determined.
• 1 cable loop = 2 feet, 3 cable loops = 2 metres.
• Application
Temperature measurement represents an important part in tank gauging
since the density of petroleum products changes approximately by 0.1 % per
degree Celsius. An error in the observed temperature will result in an error
of the correction factor, which is used to calculate the standard volume. This
electronic thermometer has been designed for field inspection of custody
transfer of bulk liquids and meets all relevant standards in the industry.
• Ambient temperature drift
SCS Surroundings Compensation System
In most cases, a Portable Electronic Thermometer (PET) will be checked
or calibrated at room temperature ambient conditions, i.e. around +20°C
(+68°F), although they can work in a wide range of operational ambient
temperatures. From areas such as Alaska to equatorial climates, these
conditions can vary over a range of around 100°C (180°F). This difference
can result in another form of drift error. The new concept named “SCS
Surroundings Compensation System” (Registered) of the Onecal
incorporates an internal reference that is constant and does not depend on
the ambient temperature over a wide operational range, i.e. from -20°C (-4°F)
to +60°C (+96°F). This means, the accuracy of the measurements made
with the Onecal is unaffected by the ambient temperature, and this error is
* Option Load 300 gr.
* Option
Fully-cushioned carrying box
This special box protects against
any damage during storage and
daily use.
• Re-calibration when exchanging the PET cable
CRC Cable Resistance Compensation
A traditional PET needs to be re-calibrated each time the cable is renewed,
as the intrinsic resistance of the cable is incorporated in the temperature
measurement sequence and any change in its value can affect the accuracy
of reading, unless the unit is properly re-calibrated. The new concept
named “CRC Cable Resistance Compensation” (Registered) of the Onecal
measures the actual resistance of the cable every time the PET is used, and
compensates for any change to eliminate this source of error. Changing the
cable, whatever length it has, will not affect the accuracy of the thermometer
and therefore does not require a re-calibration in a laboratory.
• Response time
This thermometer has a response time (time to achieve 90% of the final
temperature) of 15 seconds in water and 35 seconds in lubrication oil under
dynamic conditions.
Cable replacement without needs of
new calibration
• Maintenance
This instrument has been designed for users which require a high precision
thermometer that is always ready to operate. Users can change the cable,
the sensor or the display unit, and recalibrate it without the need of special
tools or training. The unit cannot be calibrated incorrectly.
The modular design of the
HERMetic makes the exchange of
components extremely easy and
cost efficient as no special training
or tools are required.
HERMetic Onecal without frame, 2 m (7 ft) cable
The HERMetic Onecal can also be used in laboratories for verification of existing temperature measuring
equipment. The high accuracy of this thermometer allows a reliable temperature reading. The HERMetic Onecal
can be supplied without frame and with a 2 m (7 ft) cable. This type of unit can very well be used for temperature
verification anywhere in a laboratory or on a railtrain tank if the opening is bigger than 16 mm (5/8") in order to allow
the penetration of the sensor.
Technical specifications:
Measurement range:
-40°C to 163°C (-40°F to 325°F)
Sensor temperature range:
-40°C to 200°C (-40°F to 392°F)
Ambient temperature range:
-20°C to 40°C (-4°F to 104°F)
0.1° or 0.01° selectable
Temperature scale:
°C or °F selectable
Temperature accuracy: -40°C to -30°C (-40°F to -22°F)
± 0.25°C (± 0.4°F)
-30°C to 100°C (-22°F to 212°F)
± 0.1°C (± 0.2°F)
100°C to 163°C (212°F to 325°F)
± 0.25°C (± 0.4°F)
exceeds API MPMS Chapter 7
-40°C to 163°C (-40°F to 325°F)
± 0.1°C (± 0.2°F)
Digital, one point only 0°C (32°F)
up to 9 individuals
LCD 8 digits, 10 mm character height
Approved 9 Volt battery
Battery saving:
aut. shut off /10 minutes after last action
Battery life:
Approximately 100 hours
Low battery indication:
On LCD display
Overall dim. length x width x depth: 336 x 202 x 94 mm (13.2 x 8 x 3.7 inches)
Weight with 22.8 m (75 ft) cable:
< 1.4 kg (< 3 lbs)
Probe size:
diameter: 16 mm (5/8"); length: 150 mm (6")
Probe material:
Stainless steel 1.4435
Cable length:
2 m (7.6 ft), 15.2 m (50 ft),
22.8 m (75 ft), 33.5 m (110 ft)
Cable material:
FEP Teflon jacket
Instrument protection:
IP 54
Frame material:
Antistatic Polyamide base
Electronic box material:
Coated aluminium
Temperature sensor:
PT 1000 element
Hazardous environment Approvals:
II 1 G Ex ia IIB T4 Ga
FM Approvals
CL I, DIV 1, C&D, T4 and CL I, ZN 0, AEx ia IIB T4
IECEx Ex ia IIB T4 Ga
ChinaNEPSI Ex ia IIB T4 GA
0 Ex ia IIB T4 X
Metrology approval:
PTB, portable electronic thermometer
Pattern approval
Pattern approval
The information contained in this document is subject to changes
without notice
Enraf Tanksystem SA
Rue de l’Industrie 2
1630 Bulle, Switzerland
Tel: +41 (0) 26 919 15 00
Fax: +41 (0) 26 919 15 05
E-mail: tanksystem@honeywell.com
February 2013
© 2013 Honeywell International Inc.