TDI-Dynaload Division
WCL488 Series Water Cooled Electronic Loads
Operation & Programming Manual
402828, Rev. B1
Page 35
WCL488/WCS Water Cooled Load Systems
The WCL series of water-cooled loads can be provided in a fully configured rack assembly.
There are two standard sizes available: the full size rack measuring 60 inches tall, 22 inches wide
and 36 inches deep and our Mini-rack which measures 42 inches tall by 22 inches wide by 36
inches deep. The full size rack accommodates one WCL488 master with a maximum of nine
WCS slave units (up to 120kW) and the Mini-rack accommodates one WCL488 master and up to
four WCS slave units (up to 60kW).
Each of these rack assemblies provides all the necessary power connections and water
distribution needed for full operation. A system DC disconnect is provided as a functional
disconnect and is integrated into the protection circuitry of the system. All internal AC
distribution and master/slave interconnections are also provided. The power and water inputs are
conveniently located at the rear of the rack for simplified system integration. The flow of water
through the system is closely regulated in order to maintain the proper heat sink temperature and
eliminate the possibility of condensation.
The WCS electronic load system consists of a master control unit in conjunction with up to nine
(9) slave modules. The slave modules are dependent on the master to operate. Therefore, do not
attempt to operate the slave units without a master control unit.
The WCS System is designed to automatically detect the presence of the slave units. In operation,
the control display on the master will indicate the total system rating based on number of slave
units detected. The voltage and current ranges selected will also be taken into account and
reflected in the system rating. The user may choose to operate the system with any number of
slaves. When the AC power is applied to the slave, it becomes active in the system. If the slave is
not turned on the master will not detect it and will configure the system accordingly. There is no
requirement to sequence the use of slaves. A system will operate normally regardless of which
slave unit or units are selected.
Synchronized Paralleling
The synchronized paralleling function allows the user to connect one (1) or more slave units in
parallel. The master is controlled through normal operation; the slaves are connected via a twenty
five-pin ribbon cable. For systems assembled at the factory, this cable is provided. This cable
contains all the necessary signals for the slave to respond to the master unit. In all operating
modes, the master and all slaves will share the current in proportion to the selected current range.
IMPORTANT:
Master/slave operation is intended as an extension of the current and power
capabilities when testing a single output power source. The slave units
cannot be connected to a second source or output. This will cause damage
to any or all of the loads in the system.
