Harris Atlas DVL400, Technical Manual

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2/25/03 888-2473-001 4-39
WARNING: Disconnect primary power prior to servicing.
Section 4 Theory of Operation
ATLAS Series™
4.6 Cooling System
The Atlas liquid cooling system consists of:
a.
Pump Module with optional dual pumps in main/alternate mode for redun-
dancy and the coolant reserve tank.
b.
Heat exchanger (usually mounted outside).
c.
Cooling plates or heatsinks in the transmitter.
d. Cooling system control panel which interfaces the transmitter control system
and ac power to the pump module and heat exchanger.
4.6.1 Pump Module
Drawing #843-5550-175 shows an outline drawing of a typical Atlas pump module.
The pump module is a 50/50 glycol/water pump system with the following
components:
a.
Optional dual pumps used in a main/alternate mode for redundancy.
b.
Inlet and Outlet coolant valve on each pump and an electrical isolator switch
for each pump to allow one pump to be changed while the other is still
operating.
c. A 250 liter reserve tank for the coolant.
d.
Two (2) coolant level switches
1.
Coolant Warning - Indicates low coolant level - Alarm only, system
continues to operate.
2. Coolant Fault - Tank is empty, system is shut off.
e. An in-line coolant strainer with isolating valves to allow the strainer to be
cleaned while the pump module is operating.
f. Output pressure gauge and coolant temperature gauge both visible from the
front of the unit.
g.
Drain valves for the system, the internal pipes and the reservoir tank. There is
also a drip tray in the bottom of the unit with its own drain valve.
For the following refer to the Cooling System Electrical Diagram 843-5396-865 for
3 phase or 843-5396-880 for single phase. The pump module receives its ac inputs
from the motor contactors in the cooling system control panel, K3 and K4. K3
activates Pump A while K4 activates Pump B. Each pump has an electrical isolator
switch that can be used to remove ac from the pump for servicing. The pump status
lines for the control panel pass through the 4th pole on the isolator switches S1 and
S2 which prevents an active status LED on the control panel if the isolator switch is
open. For detailed pump module and cooling system control information see "4.6.4
Pump Control Panel."