Gorman-Rupp Pumps PA4B60-4045H 1497876 and up - Manual (Page 12)

PA SERIES OM−06228
PAGE B − 5 INSTALLATION
DISCHARGE LINES
Siphoning
Do not terminate the discharge line at a level lower
than that of the liquid being pumped unless a si-
phon breaker is used in the line. Otherwise, a si-
phoning action causing damage to the pump
could result.
Valves
This pump is designed with a check valve in the
discharge line.
If a throttling valve is desired in the discharge line,
use a valve as large as the largest pipe to minimize
friction losses. Never install a throttling valve in a
suction line.
With high discharge heads, it is recommended that
a throttling valve be installed in the discharge line
to protect the pump from excessive shock pres-
sure and reverse rotation when it is stopped.
If the application involves a high discharge
head, gradually close the discharge
throttling valve before stopping the pump.
ALIGNMENT
The alignment of the pump and engine is critical for
trouble-free mechanical operation. See Section E,
Securing Intermediate And Drive Assembly To
Engine in MAINTENANCE AND REPAIR, for de-
tails.
AUTO-START
The standard pump is equipped with an auto-start
control system which allows the pump to start and
stop as the liquid level in the wet well or sump rises
and falls.
Refer to the information which follows for installa-
tion details for the liquid level sensing system pro-
vided with your pump.
Float Switch Installation
The Float Switch autostart system employs either a
single or double float switch, where a bulb raises or
lowers (floats) with the liquid level, thus activating
an enclosed miniature switch. The floats are
equipped with a socket type connector that plugs
into a matching receptacle on the auto-start control
box.
Standard floats are equipped with 50 feet (15,2 m)
of cable.
When installing the floats, note the following:
a. Be sure to provide sufficient room in the wet
well or sump so that floats do not get ob-
structed or drawn into the suction line. If a flex-
ible suction hose is used, it may be extended
to lay along the bottom of the wet well or sump
and the float can be attached to the hose
above the point where it bends along the bot-
tom. Direct the suction line toward the flow,
and the float(s) away from the flow. If a stand-
pipe is available, attach the float switch cable
to the standpipe in the sump at the approxi-
mate desired liquid level.
b. In a single float system, the cable can be teth-
ered to the suction line or standpipe approxi-
mately 6 inches (152 mm) above the float.
This setting allows approximately 9 inches
(229 mm) of liquid rise between pump start/
stop. The start/stop interval may be increased
by extending the float end of the cable. The
liquid level in the sump will increase approxi-
mately 8 inches (203 mm) between start/stop
intervals for every 6 inches (152 mm) of cable
increase.
c. If a double float switch system is used, posi-
tion the Start" float at the desired high water
level in the sump, and the Stop" float at the
desired low water level in the pump.
d. Refer to Figure 3 for additional float switch
data.