ITT HYDROVAR Series User Manual

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Connection example:
The following wiring diagram shows a standard cascade control system where the
HYDROVAR is fitted with an additional Relay card, in selected mode “Cascade Relay”.
To switch the fixed speed pumps via the internal relay card, an external panel for the
contactors of the D.O.L or STAR/DELTA starters (and optional A/0/M – switch) is required.
In the example below 3 fixed speed pumps (motors) are connected to the Relay Card. For
such an application, an optional HAND/OFF/AUTO switch (SW1, SW2, SW3) is
recommended.
- During normal operation the switch is set to AUTO, so the Relay Card of the HYDROVAR
would start and stop the follow-up pumps.
- The “HAND” position allows a manual operation of the pumps.
- If one of the additional switches is in OFF position, the related relay must be disabled in
the submenu STATUS [20] to ensure correct operation of the multi-pump system.

ITT HYDROVAR Series Specifications

General

Brand	ITT
Model	HYDROVAR Series
Category	Control Unit
Language	English