Chromalox PD422-4 Electric Heater User Manual


 
INSTALLATION
ELECTRIC SHOCK HAZARD. Disconnect all power
before installing or servicing heater. Failure to do so
could result in personal injury or property damage.
Heater must be installed by a qualified person in
accordance with the National Electrical Code, NFPA
70.
1. Before installing the PTH heater, inspect it thoroughly for
possible damage which may have occured during shipment. Also
check to insure that the line voltage is the same as that stamped on
the heater nameplate.
2. Where work will pass over or near equipment, additional pro-
tection such as a metal guard may be needed.
3. To resist buoyancy and to keep the heater in close profile with
tank wall, a metal bracket with two mounting holes has been pro-
vided.
4. IMPORTANT: Heated section (See Figure 1, “B” Dimension)
must be totally immersed at all times. If the heater is not properly
submerged, it will overheat and damage the heating elements and
create a possible fire hazard due to excessive sheath temperatures.
5. Heater must not be operated in sludge.
FIRE HAZARD. Since heaters are capable of develop-
ing high temperatures, extreme care should be taken
to:
A. Avoid installing heaters in an atmosphere containing com-
bustible gases and vapors.
B. Avoid contact between heater and combustible materials.
C. Keep combustible materials far enough away to be free of
the effects of high temperatures.
WIRING
ELECTRIC SHOCK HAZARD. Any installation involving
electric heaters must be performed by a qualified per-
son and must be effectively grounded in accordance
with the National Electrical Code to eliminate shock
hazard.
1. Electrical wiring to heater must be installed in accordance
with the National Electrical Code or local codes by a qualified per-
son.
2. When element wattages are not equal, heaters must not be
connected in series.
3. For single phase, apply power across two (2) black leads.
Green wire (ground) must be properly grounded.
4. For balanced 3 phase loads, three (3) heaters of the same volt-
age and wattage ratings are required. A six-step guide to wiring
connections for 3 phase delta:
A
A
A
A
#1#1
B
B
B
B
BBA A
#2
#2
#3
#3
A
A
A
A
#1
#1
#1
B
B
#2
#2
#2
#3
#3
#3
Step 1: Designate one
black leadwire as “A” and
one black leadwire as “B”.
Step 2: Assign designations
1, 2, 3 to heaters.
Step 3: Connect leadwire “A”
of Heater #1 to leadwire “A”
of Heater #2.
Step 4: Connect leadwire “B”
of Heater #1 to leadwire “B”
of Heater #3.
Step 5: Connect leadwire “B”
of Heater #2 to leadwire “A”
of Heater #3.
Step 6: Connect one 3 phase
power line to each of the
three connections.
Three Phase
Power
Note: Green wire (ground) of each heater must be properly grounded.