The unit does not carry a failsafe circuit bypass for the evaporator fan in the event of a VFD
malfunction. During a VFD failure, the evaporator fan becomes nonoperational. If there is a
demand for cooling, the unit compressors continue to run until the low pressure safety switch trips.
Factory shipped
Units that are 8 tons or larger ship with a VFD controller factory installed and wired in the
evaporator (air handler) corner post. See the dimensional drawings in the IOM for the location.
DSV models
The DSV units ship factory split (condenser and evaporator) and require assembly in the field. The
motor is pre-wired to the VFD in the factory.
To assemble the DSV model in the field:
1. Plug the low voltage wiring, shipped wired to the VFD, to the SE Controller.
2. Connect the low voltage wires from VFD unit (24VDC) to the evaporator fan VFD relay
(EVFDR). The EVFDR relay acts as a switch to turn on the VFD.
3. Connect two 1/4 inch Q.C. to common and normally open positions (red wire to “C,” orange
wire to “NO”).
The VFD switch runs on 24VDC.
CAUTION
Do not cross 24VAC and 24VDC wiring on EVFDR relay.
DSH models
The VFD controller on DSH units is factory wired. The evaporator fan power conductors are factory
wired to the distribution block. The control wiring for field split applications needs to be field
provided and routed from condenser to evaporator.
CSV models
The CSV units ship factory assembled except for the CSV240 which can optionally be split and the
CSV300C which ships split (condenser and evaporator) and requires assembly in the field. The
motor is pre-wired to the VFD in the factory.
To assemble the CSV300C model in the field:
1. Plug the low voltage wiring, shipped wired to the VFD, to the SE Controller.
2. Connect the low voltage wires from VFD unit (24VDC) to the evaporator fan VFD relay (EVF-
DR). The EVFDR relay acts as a switch to turn on the VFD.
3. Connect two 1/4 inch Q.C. to common and normally open positions (red wire to “C,” orange
wire to “NO”).
The VFD switch runs on 24VDC.
9
VFD for D-Series (DSV/DSH) Air-cooled Self-Contained Units, and C-Series (CSV) Water-Cooled Self-Contained Units,
C-Gen
Johnson Controls
