Emerson Mobrey Hydratect 2462 User manual

Reference Manual
24625020, Rev AA
March 2017
Mobrey™Hydratect 2462
Steam/Water Detection System

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Reference Manual
24625020, Rev AA
Title Page
March 2017
Title Page
Mobrey™Hydratect 2462
Read this manual before working with the product. For personal and system safety, and
for optimum product performance, make sure you thoroughly understand the
contents before installing, using, or maintaining this product.
Failure to follow these guidelines could result in death or serious injury.
Avoid contact with the leads and terminals. High voltage that may be present on leads
can cause electrical shock.
Explosive atmospheres
Never operate the equipment, or any sensors connected to the equipment, in a
potentially explosive atmosphere. It is not intrinsically safe and could possibly cause an
explosion.
Grounding
To minimize the hazard of electrical shock, it is essential that the equipment be
connected to a protective ground (earth) whenever the power supply, measurement,
or control circuits are connected, even if the equipment is switched off.
The electronics unit must be connected to ground (earth) using the marked case stud
before control or signal leads are connected. The ground (earth) connections must
have a current rating of 25 A.
Avoid using unsafe equipment
The equipment may be unsafe if any of the following statements apply:
Equipment shows visible damage.
Equipment has failed to perform an intended operation.
Equipment has been stored in unfavorable conditions.
Equipment has been subjected to severe physical stress.
If in any doubt as to the serviceability of the equipment, do not use it. Get the
equipment properly checked by a qualified service technician.
Live electrical wires
When the equipment is connected to a power supply, the opening of covers or removal
of parts could expose live electrical wires.
The equipment must be disconnected from all power and signal sources before it is
opened for any adjustment, replacement, maintenance, or repair.
Adjustment, maintenance, and repairs must be must be done by qualified personnel.
DO NOT OPEN THE ELECTRONICS UNIT WHEN IT IS ENERGIZED.
Equipment modification
To avoid introducing safety hazards, never install non-standard parts in the equipment,
or make any unauthorized modification. To maintain safety, always return the
equipment to Rosemount Measurement Limited for service and repair.

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The equipment described in this reference manual has been designed in accordance
with EN61010 “Safety requirements for electrical equipment for measurement,control
and laboratory use”, and has been supplied in a safe condition.
The equipment is designed solely for electronic measurement and should be used for
no other purpose. Rosemount Measurement Limited accepts no responsibility for
accidents or damage resulting from failure to comply with these precautions.
Cleaning
To clean the instrument, use a damp cloth with a mild, water-based cleaner. Clean the
exterior of the instrument only. Do not allow liquids to enter or spill onto the
instrument.
Mains ac power supply
Never operate the equipment from a line voltage or frequency in excess of that
specified. Otherwise, the insulation of internal components may break down and cause
excessive leakage currents.
To allow the electronics unit to be isolated from the ac supply, the supply must be
routed through a switch (or circuit breaker). The switch (or circuit breaker) must be
within easy reach of the operator and must be clearly identified as the means of supply
isolation. The maximum current drawn from the supply must be limited by a fuse or
trip, to a maximum of 13 A.
Fuses
Before switching on the equipment, check that the fuses accessible from the interior of
the equipment are of the correct rating. The rating of the ac line fuse must be in
accordance with the voltage of the ac supply.
Should any fuse continually blow, do not insert a fuse of a higher rating. Switch the
equipment off, clearly label it “unserviceable” and inform a service technician.
Not designed for nuclear-qualified applications
The products described in this document are not designed for nuclear-qualified
applications. Using non-nuclear qualified products in applications that require
nuclear-qualified hardware or products may cause inaccurate readings.
For information on Rosemount nuclear-qualified products, contact your local Emerson
Process Management Sales Representative.

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24625020, Rev AA
Table of Contents
March 2017
Table of Contents
Contents
1Section 1: Introduction
1.1 Using this manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Product recycling/disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.3 What the Hydratect 2462 does . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.3.1 Steam and water detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3.2 Contamination detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3.3 Fail-safe operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.4 The Hydratect 2462 variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.5 Typical applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.5.1 High water level detection in a drain pot . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.5.2 Water level detection in a boiler drum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.6 How electrodes operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.6.1 Conductivity and resistance values of steam and water . . . . . . . . . . . . . . . 7
1.6.2 The signal returned by the electrode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.6.3 LED and relay states for electrodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2Section 2: Installing the electrodes
2.1 Electrode installation methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
2.2 Mounting an electrode to an insert. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
2.2.1 Welding the electrode insert to a pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
2.2.2 Fitting the electrode-insert cover (part one) . . . . . . . . . . . . . . . . . . . . . . . . 13
2.2.3 Fitting the electrode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.2.4 Fitting the electrode-insert cover (part two) . . . . . . . . . . . . . . . . . . . . . . . .16
2.3 Mounting electrodes on a manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
2.4 Customized manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
3Section 3: Installing the Electronics Control Unit
3.1 Installation summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
3.2 Fitting cable glands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
3.3 Mounting the Hydratect 2462 Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
3.4 Setting the printed circuit board (PCB) jumpers . . . . . . . . . . . . . . . . . . . . . . . . . .23
3.5 Connecting the electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
3.5.1 Preparing the electrode cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.5.2 Preparing the fault and status relay cable
(for the Hydratect 2462A and 2462C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

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3.5.3 Preparing the fault and status relay cables
(for the Hydratect 2462E) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
3.5.4 Preparing the power supply cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3.5.5 Connecting the prepared cables to the front panel . . . . . . . . . . . . . . . . . . 37
4Section 4: System Testing
4.1 Test summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
4.2 Testing the electrodes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
4.2.1 Suggested test for water-normal setting . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
4.2.2 Suggested test for steam-normal setting . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5Section 5: Electrodes Servicing
5.1 Service summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
5.1.1 Safety precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
5.2 Periodic check. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
5.3 Repairing an electrode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
5.4 Periodic system overhaul . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
5.5 Electrode replacement parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
6Section 6: Electronics Servicing
6.1 Fault diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
6.2 Correcting a fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
6.2.1 Correcting a power loss fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
6.2.2 Correcting electrode connection faults . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
6.3 Electrode contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
6.4 Electronic component failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
6.5 Electronic replacement parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
A.1 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
A.1.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
A.1.2 Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
A.1.3 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
A.1.4 Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
A.1.5 Environmental. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
A.1.6 Approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
A.2 Dimensional drawing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58

Reference Manual
24625020, Rev AA
Introduction
March 2017
1
Introduction
Section 1 Introduction
1.1 Using this manual
The sections in this manual provide information on installing, operating, and maintaining
the Mobrey™Hydratect 2462. The sections are organized as follows:
Section 2: Installing the electrodes contains the procedures for mounting electrodes to a
pipe or manifold.
Section 3: Installing the Electronics Control Unit contains the mechanical and electrical
installation procedures.
Section 4: System Testing contains procedures to check the operation of the Hydratect 2462
system after installation completion or any configuration change.
Section 5: Electrodes Servicing describes the electrode servicing procedure that must be
followed to ensure continued and trouble-free operation of the Hydratect 2462 system.
Section 6: Electronics Servicing contains fault-finding and fault-correction procedures for the
electronics control unit.
Section A: Specifications and Data contains specifications and other reference data, including
dimensional drawings.
1.2 Product recycling/disposal
Recycling of equipment and packaging should be taken into consideration and disposed of
in accordance with local and national legislation/regulations.
1.3 What the Hydratect 2462 does
The Hydratect 2462 system is the electronic alternative to conventional water level
switches on steam-raising plant. The system contains a compact, two-channel electronic
control unit connected to a pair of electrodes that are mounted in the plant pipe-work
(See Figure 1-1 on page 2).
Each of the two channels gives independent indications of the presence of water or steam
that are much more reliable than those obtained with conventional electro-mechanical
devices. The electronics control unit provides a local indication of steam, water, and fault
states, and has configurable fault- and trip-outputs.
Typical applications of the Hydratect 2462 system are:
Drain pots.
Water detection in steam lines.
Low- or high-level water detection.
Wherever it is necessary to detect water or steam.

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Introduction
Figure 1-1. The Hydratect 2462 Electronics Control Unit
A. Wall mounting brackets (lugs). C. Alarm and trip signal output.
B. M6 earthing/grounding stud.
Front view of electronics control unit
B
A
Example of Hydratect 2462 system with the
electronics control unit, and horizontal pipe run
with mounted electrodes and covers.
C

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Introduction
1.3.1 Steam and water detection
On each of the two electrically-isolated channels, the Hydratect 2462 system detects steam
and water by using the differences in their resistance and conductivity (Figure 1-5 on
page 7).
Detection of steam and water is indicated by the illumination of a red or green LED on the
front panel of the Hydratect 2462 Electronics Control Unit (Figure 1-1 on page 2).
The Hydratect 2462 system also provides status outputs from relays (one per channel) to
indicate the detected states. Each status relay has normally-open and normally-closed
electrical contacts to control external equipment.
Each Hydratect channel is individually set to a water-normal or steam-normal state by using
configuration ‘jumpers’(1) on a printed circuit board (PCB). The ‘jumpers’ must be set to
correspond with the normal state of the system. This allows the status relays to default to
the not-normal state if the Hydratect 2462 system developed a fault. For example, a status
relay is de-energized when a steam-normal channel monitoring a steam line detects water
(i.e. a not-normal state). In that situation, the normally-open relay contacts close and the
normally-closed contacts open. A latch option is available for each status relay, which, once
activated, holds the relay in the not-normal state until reset.
See “Setting the printed circuit board (PCB) jumpers” on page 23 for further information.
1.3.2 Contamination detection
To prevent a build-up of contamination causing a false indication, a contamination
detection circuit operates in parallel with the steam/water detection.
An error threshold for the contamination detection circuit can be set for high sensitivity or
low sensitivity by using ‘jumpers’ on a PCB. The circuit can be switched off if not required.
See “Setting the printed circuit board (PCB) jumpers” on page 23 for further information.
Detected contamination on a Hydratect channel is indicated by the front panel fault LED,
and a fault relay (one per channel) is de-energized for use by external equipment.
1.3.3 Fail-safe operation
For reliability, each Hydratect channel has a separate power supply.
The Hydratect 2462 system continuously monitors itself for component failure, cable faults,
ground (earth) faults, and electrode problems. Components outside the self-monitoring
loop are in triplicate such that if two were to fail, the system would still function normally.
Component failures are indicated by the front panel fault LED and cause the fault and/or
status relays to be de-energized.
Hydratect 2462 system self-checking includes the signal and ground (earth) cable
terminations at the electrodes. The fault LED is illuminated and the fault relay is
de-energized if one or more conductors become detached.
The ways in which the LEDs and relays indicate the system state are summarized in
Table 1-2 and Table 1-3 on page 9.
1. A PCB ‘jumper’ is a metal bridge that closes an electrical circuit. Typically, a ‘jumper’ consists of a plastic plug that fits over a pair of
protruding pins. By placing a jumper plug over a different set of pins, you can change a board's parameters.

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Electrode signals, status outputs (relays), and fault outputs (relays) can be validated by
connecting both Hydratect channels in a 'one-out-of-two' or 'two-out-of-two' tripping
scheme. Typical applications are shown in Figure 1-3 on page 6 and Figure 1-2 on page 5.
Further information is in Section 3: Installing the Electronics Control Unit.
1.4 The Hydratect 2462 variants
The Hydratect 2462 Electronics Control Unit is available in three standard configurations,
as listed in Table 1-1.
Table 1-1. Hydratect 2462 Variants
1.5 Typical applications
1.5.1 High water level detection in a drain pot
Figure 1-2 on page 5 shows a system for detecting a high water level in a drain pot attached
to a superheat steam line. In this system example, a Mobrey In-line Manifold with two
electrodes are used to detect the same level.
The electrode outputs of both Hydratect channels (1 and 2) are connected in a
'one-out-of-two' configuration inside the electronics control unit. Both channels can then
indicate a high water level, providing an element of safety if one of the two electrodes fail.
Model
Supply Relay output
Mains a.c. d.c. SPST relays(1)
1. Single Pole Single Throw (SPST) relays have Normally Open (NO) and Normally Closed (NC) contacts.
DPCO relays(2)
2. Double Pole Change Over (DPCO) relays have two sets of Normally Open (NO), Common (C), and Normally Closed (NC)
contacts.
2462A  
2462C  
2462E   