13-9-663 Page 21
PARALLEL PIPING
(Figure 2-8, page 20) - A separate water control valve is required to control the
discharge air temperature. If a remote (externally mounted) water-cooled aftercooler is piped in parallel
with the heat exchanger, provide a separate water control valve for the aftercooler and pipe separate inlet
water lines to both the aftercooler and heat exchanger.
The water control valve is to be adjusted to maintain oil out of the heat exchanger within the 140
°
F to
150
°
F (60
°
C to 66
°
C) range regardless of inlet water flow or temperature as long as a minimum flow for
a given temperature is met (
Figure 2-5
, page 18, and
Figure
2-6
, page 19. See Section 5 for adjustment instructions and maximum allowable lubricant
temperature.
ELECTRICAL WIRING - Standard Units
- The Gardner Denver Rotary Screw compressor is factory
wired for all starter to motor and control connections for the voltage specified on the order. It is necessary
only to connect the unit starter to the correct power supply. The standard unit is supplied with an open
drip-proof motor, a NEMA 12 starter and control enclosure. See Section 2, “Location” paragraph, for
distance to the nearest obstruction on starter and control box sides of the unit.
Lower operating voltages (200/208) require that the unit starter be remote mounted since the starter is too
large to be mounted within the control enclosure. If not supplied with the compressor unit, the starter is to
be a size 6 full voltage non-reversing type in NEMA (CEMA) enclosure suitable for the environment, with
two (2) rejection type control circuit fuses (size according to motor starter manufacturer’s standard), a 200
(208) volt coil, and three (3) overload heaters for 200 (208) volt 100 HP (75 kW), 1.15 service factor
motor.
The overload heaters are to be selected according to starter manufacturer’s tables based on motor
nameplate full load amperage.
Electrical shock can cause injury or death. Open main disconnect switch,
lockout and tagout before working on control box.
GROUNDING
- Equipment must be grounded in accordance with Table 250-95 of the National Electrical
Code.
Failure to properly ground the compressor package could result in injury or
death. Install ground wiring in accordance with the National Electrical Code
and any applicable local codes.
