Teikoku DynaPump LE Series, Instruction Manual

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RECOMMENDED
Install properly sized pressure gauges in
suction and discharge lines near the pump
ports so that operation of the pump and
system can be easily observed. Should cavi-
tation, vapor binding, or unstable operation
occur, widely fluctuating discharge pres-
sures will be observed.
Such gauges provide a positive means of determin-
ing actual system conditions and can be used to
great advantage in evaluating system problems.
2-3. Electrical
2-3.1. General
Except where indicated, all Dynapump LE Series are
started with full line voltage. Refer to Paragraph 3-3,
Page 9, for checking direction of rotation. Also see
Wiring Diagram Figure 2-1, Page 7 for proper wiring
connections.
2-3.2. Thermal Cutouts
All Dynapump LE Series are fitted with a thermal
cutout. The cutout is a heat-sensitive bimetallic
switch mounted in intimate contact with the stator
windings. The TCO wiring diagram is shown in Fig-
ure 2-1, Page 7. Maximum holding coil currents is
3.1 AMPS for 115 volts.
WARNING
Do not connect TCO in series with main
power lead. Excessive heat build up in the
winding area opens the normally closed
thermal switch, which, in turn, opens the
holding coil circuit, shutting off power to
the pump. Be sure to connect the thermal
cutout as required.
Thermal cutouts in Class H insulated motors are
set to open at 356
o F (180 o C). If the motor cuts out
because of TCO action, there will be a time delay
before the motor can be restarted. The motor must
be restarted manually.
DO NOT RESTART UNTIL YOU DETERMINE THE
CAUSE OF THE OVERHEATING.
Page 6
WARNING
The thermal cutout switch does not provide
protection against fast heat build-up result-
ing from locked rotor conditions, single
phasing or heavy overloads. The current
overload relay heaters in the magnetic
starter must provide for this protection. The
rating of the heaters should be high enough
to avoid nuisance cut outs under running
loads, but must not be oversized. Refer to
Table 2-1, Page 7, for starting and running
electrical characteristics. It is recom-
mended that “quick trip” (Class 10) heat-
ers be used because of the more rapid re-
sponse time.
2-3.3. Starting Equipment
Motor starters (normally not supplied with Dynapump
LE Series) should be sized to handle the load re-
quired. Full Load HP, Full Load Amps and Start KVA
Data is listed in Table 2-1, Page 7.
Heaters in the starters should be sized for the am-
perage shown on the Dynapump LE Series name-
plate. DO NOT size heaters in excess of 10% of full
load amp rating. In order to provide complete protec-
tion for Dynapump LE Series motors under all con-
ditions, it is recommended that “
quick trip ” (Class
10) type heaters be used in the starters where avail-
able. Standard heaters provide adequate protection
for Dynapump LE Series motors under starting or
normal running conditions, but require a greater
length of time than “
quick trip ” type heaters to cut out
if the motor is subject to locked rotor or overload
conditions.
CASE I - 460 Volt, 3-Phase Dynapump LE Series (See
Figure 2-1, Page 7).
Typical 3-phase across-the-line magnetic starter with
start-stop push button station shown.
Thermo switch (thermal cutout inside Dynapump LE
Series motor) is wired as shown in Figure 2-1, Page
7.
Be sure to size heaters properly. Motor data can be
found on the pump nameplate.