nvent RAYCHEM HHS-WWH User manual

DESCRIPTION
The nVent RAYCHEM Hopper Heating System Wrap-Wound Heater
(HHS-WWH) is designed for the poke tube and throat portions of
Electrostatic Precipitator (ESP) hoppers, baghouse hoppers and
material / dust-collector hoppers and is intended to complement the
HHS heater modules.
It is highly recommended for all HHS-WWH heaters to be used in
conjunction with a temperature control device. These instructions
describe the procedure for installation, storage and handling of
HHS-WWH heaters. Carefully follow all directions.
For technical assistance, contact nVent at [email protected]
The HHS-WWH heater must be
installed correctly to ensure proper
operation and to prevent shock
or fire. Read these important
warnings and carefully follow all the
installation instructions.
• All electrical wiring must follow
local electrical codes. Ground fault
equipment protection must be used
on each heater branch circuit to mini-
mize the danger of re if the heater
is damaged or improperly installed
and to comply with nVent design
requirements, agency certications
and national electrical codes.
• Damaged heaters and connections
must be replaced. Do not attempt to
repair or energize if damaged. Only
qualied personnel are allowed to
connect electrical wiring. Disconnect
all supply power at the source before
making any power connections. It is
highly recommended to never oper-
ate heaters without a temperature
control device.
• The end-user is responsible for
providing a suitable disconnecting
device.
• The end-user is responsible for
providing a suitable electrical
protection device.
• Final installation / wiring is to be
inspected by the authority who
has jurisdiction in the area that the
heater is installed.
• Approvals and performance are
based on the use of specified parts
only. Do not use vinyl electrical
tape or substitute parts.
• Read and understand this entire
manual before operating this elec-
tric heater. Leave these installation
instructions with the user for future
reference.
• Failure to observe these warnings
may result in personal injury or
damage to the heater.
Read and understand this entire manual before operating or servicing these heaters. Failure to understand how to
safely operate these heaters could result in an accident causing serious injury or death. These heaters should only be
operated by qualified personnel and any individual who has not read and understood all installation instructions is not
qualified to install this product. Additional copies of this manual are available upon request.
WARNING:
WARNING: CAUTION:
• Never handle the heater while it is in operation; always
disconnect the heater from the power source and allow
for proper cooling prior to handling.
• Inspect heater before use and do not use a heater with
torn or worn surfaces.
• If spillage of foreign matter onto the heater occurs,
disconnect from the power source and clean after the
heater is allowed to cool.
• Never operate a heater without an appropriate heat
sink. (Device being heated is considered a heat sink).
• Do not operate the heater above the rated temperature
value.
• Fasten the heater to the heated surface using approved
methods only.
• Do not repair damaged or faulty heaters.
• Do not crush or apply severe physical stress on the
heater or lead wire assembly.
• Avoid hazards or unsafe practices which could result in
personal injury or property damage.
LIMITED WARRANTY
nVent offers 1 year limited standard warranty for the RAYCHEM
HHS-WWH.
ADDITIONAL / OPTIONAL MATERIALS REQUIRED
• Cleaning / prep supplies
• Wire ties
• Junction box
• Temperature controller and sensor
• Insulating materials
SAFETY ALERT SYMBOL
The symbol above is used to call your attention to instructions
concerning your personal safety. It points out important safety
precautions. It means “ATTENTION! Become Alert! Your Personal
Safety is involved!” Read the message that follows and be alert to
the possibility of personal injury.
HHS-WWH PRODUCT SPECIFICATIONS
Power density Standard wattages up to 4650 W/m²
(3.0 W/in²)
Voltage range (nominal) 120 to 600 VAC
Maximum exposure
temperature
760ºC (1400ºF)
Maximum maintain
temperature (power on)
500°C (932°F)
Minimum installation
temperature
–20ºC (–4ºF)
Typical heater set point 120-150ºC (248-300ºF)
Dielectric strength Up to 2,200 VAC
Power leads* 5.0m (16 ft.) long, moisture resistant,
high-temperature stainless steel overbraid
with a standard heater ground wire
* Lead wire length can be customized to align with the project
design requirements.
HHS-WWH
Hopper Heating System – Wrap-Wound Heater Installation
Instructions

2 | nVent.com
HOPPER SURFACE PREPARATION
HHS-WWH STORAGE
1. Keep each heater in its original packaging until you are ready to
install it.
2. Store the box in a cool, dry environment.
3. Avoid stacking heavy objects on the box, which could damage
the HHS-WWH heater.
4. If any heaters are exposed to moisture, please contact nVent
technical support.
1. Inspect the hopper surface. To provide maximum heat
transfer efficiency, verify the installation area is free of:
• Sharp edges or protrusions (weld splatter, rough
seams, etc.)
• Rust and corrosion
• Grease and oil
• Obstructions, such as instrument lines, electrical wiring
or conduit, hopper support, or reinforcements
2. The heater surface should be clean prior to installing the
heaters.
3. Check that the desired placement of the heater will not cause
damage to the heater through impact shock or by neighboring
moving parts.
HEATER PREPARATION
1. Check for suspected damage to the HHS-WWH heater prior
to installation and document any identified damages for
settlement with the delivery service. Do not install the heater if
it is damaged.
2. Verify that all parts are received against the packing list.
3. Confirm voltage / wattage rating of the heater is appropriate
for the power supply device or temperature controller as
the heater is designed to work at a specific voltage to heat
properly. For additional information, contact nVent.
4. Confirm that the heater maximum exposure temperature
rating is suitable for the environment. The temperature of the
internal heating element may run up to 25% higher than the
external surface of the outer sheath.
5. HHS-WWH exposure temperature range: –20ºC to 760ºC
(–4ºF to 1400ºF)
• HHS-WWH maximum continuous exposure / maintenance
temperature: 500ºC (932ºF)
• HHS-WWH maximum intermittent exposure temperature
(power off): 760ºC (1400ºF)
HHS-WWH HANDLING
1. All HHS-WWH heaters are usually packaged with each
respective hopper. Utilize the layout drawings to match and
position each respective heater to the correct hopper.
2. To avoid mechanical damage do not lay the heater where it can
be stepped on or struck by tools or equipment.
IMPORTANT: This heater is an electrical device. Handle
it with the same care you would use with any electrical
device and carefully follow these instructions.
Do not install any damaged heaters. If a heater is
damaged, replace the complete heating module and
cold leads.
• Do not immerse the heater in liquid.
• Keep volatile or combustible materials away from
the heater when in use.
• Use the heater only in approved locations. • Keep sharp metal objects away from the heater.
Failure to observe these warnings may result in
electric shock, risk of re, and personal injury.
DANGER:

nVent.com | 3
HEATER INSTALLATION
Ensure the hopper surface is clean before securing the
HHS-WWH to the hopper. The flexible heater can be installed
on both a flat and/or curved surface. For a flat surface, lay the
heater onto the surface to be heated. For a curved surface, wrap
the heater onto the surface to be heated. The length of one
entire side of the heater must be in full contact with the surface.
IMPORTANT: The HHS-WWH heater must be installed with
good contact to the hopper surface. Inadequate contact may
result in lower heater eciency. It is highly recommended to
connect the HHS-WWH heater to an external temperature
control device, and it is not recommended to turn on the
heater without a temperature controller. During installation,
heaters should not be left exposed to rain, snow or moisture.
It is recommended to perform a heating system inspection
and the necessary electrical tests before thermally insulating
the heaters.
IMPORTANT: Reference H59848 for the separate Hopper
Heating System (HHS) installation instructions.
CONNECTING TO A POWER SOURCE
The heater must be connected to an external control device and
should be operated with some form of temperature control.
1. Install and connect the primary temperature control device
as shown in the installation instructions. The wiring
schematics provided on the next page are for reference only.
See nVent project specific heater layout and wiring drawings
for actual heater wiring.
2. De-energize all power sources before connecting heaters.
The heater ground is the lead wire with green insulation.
Ensure that the lead wires can reach the distance to the
terminal / junction box.
3. The heater is designed to operate at a specific voltage ±10%.
Refer to the label on the heater for the proper operating voltage
and wattage information. Failure to operate the heater at the
specified voltage could result in overheating of the heated
surface, or personal injury. Also note lower-than-rated voltage
will result in under-heating.
4. All electrical connections must be made by qualified personnel
and in accordance with all applicable codes
and regulations. Proper Personal Protective Equipment (PPE)
should be utilized during installation. Component approvals
and performance ratings are based on the use of nVent
specified parts only.
5. Ensure the heater is protected by a properly rated circuit
breaker or fuse as specified on the design or installation
drawing.
6. Two lead wires (same color) should be connected to the
power source (or temperature control device) directly, through
a junction box, or to a connector that is mated to a receptacle
connected to the power source. HHS-WWH heaters are
non-polarized, allowing either wire to be connected to the
neutral or hot. The third wire (if applicable), designated by
the color green (or a green stripe) should be connected to
the ground wire.
7. Locate the temperature sensors exactly as per the
project drawings.
Ensure the heater is not kinked or twisted; or that any portion of
the heater is hanging free from the surface. Do not overlap the
HHS-WWH heater on itself.
Attach the heater to the surface by using the mechanical wire
ties, as supplied in the standard HHS-WWH bill-of-materials.
Ensure that the attachment method does not cause damage
to the heater.

4 | nVent.com
GROUND FAULT PROTECTION
CONNECTING HHS-WWH HEATERS IN PARALLEL
All HHS-WWH heater circuits are required to be protected with a ground fault circuit interrupter (GFCI). This device will minimize the
risk of fire or shorting by shutting off the power to the circuit whenever a significant ground-fault current is detected. Suitable circuit
breakers with ground-fault protection can be purchased through nVent.
ContactorThermostat
Power Supply 415V/230VAC
L2 N
L1
HHS-WWH
CONNECTION DIAGRAM WITH CONTACTOR
Power Supply 240VAC
N
L
HHS-WWH
CONNECTION DIAGRAM WITH THERMOSTAT
HHS-WWH SYSTEM CONTINUITY AND ELECTRICAL INSULATION RESISTANCE (MEGGER) TESTS
Continuity of each heater should be checked upon removal from packaging and again after installation. Verify that the measured
resistance in ohms agrees with the value printed on the label (with a +/- 10% measured resistance tolerance at 20ºC). Electrical
insulation resistance (IR) should be checked on each heater unit after installation; measure the resistance between the heater
element lead wires and a nearby ground point (e.g., metal heater cladding or welded stud on the hopper wall) at 500 VDC for 1
minute. All IR values should be greater than 20 megaohms.
IMPORTANT: Ground fault protection devices, although required are not normally displayed in typical single or parallel
wiring diagrams similar to those shown above. Contactors in the diagrams shown above should be controlled by a temperature
control device.
HHS-WWH SYSTEM PERFORMANCE TESTING
This test verifies that the system is working properly.
1. When the heaters and controls are installed and connected to
power, and the hopper surface is thermally insulated, turn the
circuit breaker on.
2. Set the primary temperature control device temperature about
20°C higher than the maintain / ambient temperature. This
action energizes the heaters.
3. Allow the heater(s) to be powered for about five minutes,
then measure the voltage and current. Note these values
in the maintenance log as a reference for future
maintenance checks.
4. Lower the temperature control device set point to ensure that
the heater shuts off.
5. Switch off.
6. Set the primary temperature control device to the desired
set point.

nVent.com | 5
SYMPTOM POSSIBLE CAUSE SOLUTION
1. No heat / No current A. Loss of power (voltage) A. Restore power to the heater circuit (check
circuit breaker and electrical connections).
Terminations, if not done properly, can cause
EPD-type breakers to trip unexpectedly
B. Controller set point too low B. Adjust set point
C. Heater “Open” C. Check the resistance measurement between
the two lead wires. If no reading, repair or
replace the heater
D. Controller failure D. Repair the sensor or controller
2. Circuit breaker tripping A. Circuit breaker underrated A. Verify rating of the circuit breaker with respect
to the heater output. If breaker is underrated,
replace the breaker
B. Ground fault B. Check insulation resistance between power
leads and the ground lead of the heater. If the
value is less, replace the heater
3. Low system temperature A. Controller set point too low A. Adjust set point
B. Temperature sensor located too close to
the heater
B. Relocate sensor
C. Wet insulation material and / or insulation
thickness is different than designed
C. Replace insulation; increase insulation
thickness (if dry)
D. Low voltage (check at power connection point) D. Adjust voltage to meet design requirements
4. High system temperature A. Controller “on” continuously A. Adjust set point or replace sensor
B. Controller failed with contacts closed B. Replace the temperature controller
HHS-WWH SYSTEM MAINTENANCE AND TROUBLESHOOTING
It is the responsibility of the end user to ensure that the
final installation meets all local, state and federal codes and
regulations. Please read this manual prior to contacting
nVent, as this manual is designed to answer the most commonly
asked questions.
If you are unable to identify the problem or need additional
assistance, please contact nVent at
[email protected] .
Perform a continuity test on each HHS-WWH heater at least
once a year. The frequency of inspections and tests should
depend on the severity of the environment and operating
conditions. Where multiple heaters are connected in parallel,
disconnect and individually test each heater.
A performance test should also be done once a year. Check
the temperature control device at that time. Things to look for
include the following:
• Control switching at the proper temperature.
• Signs of corrosion around or near the lead wire
connection point.
• Any mechanical damage to the heating element.