Feature Notes
Air Handing Unit Cascade Submodule with 3 x Relay Outputs
CAS / DIN / AHU /...
Main Features Adds up to 3 additional stages of Cooling or Heating to an AHU Controller Automatic Interlocks with AHU

Description of Features

General

This AHU Cascade Module is an AHU Submodule, and must be used in conjunction with a SeaChange AHU Controller; it can be used to add up to 3 additional stages of heating or cooling to the sequence controlled by the AHU Controller .The AHU Controller has 4 on-board relays to control 2 stages of heating and/or cooling (see AHU Controller Data Sheet). An AHU Controller can have one Cascade Module for Heating, and one for Cooling registered to it (see “Registration”); thus an AHU Controller can control a maximum of 5 stages of Heating and/or Cooling.

Typical Application

Staged Heating that is unrelated to an AHU (e.g. some Terminal Units) may be controlled using an Actuator Controller - see appropriate Data Sheet.

Interlocks with AHU Fans

The AHU Controller determines when the additional stages controlled by the Cascade Module will run; all interlocks that are present for the 2 on-board stages of the AHU Controller (e.g. Fans start before electric batteries are enabled) are automatically used by the Cascade Controller - see AHU Controller Data Sheet for full details.

Registration

Registration is the simple process by which logical connections are made between Controllers in a SeaChange system; it is done at time of commissioning and involves pressing buttons on the Controllers in a specific sequence (for further details of the registration process, see our publication “Commissioning Guide”).

The Cascade Module must be registered to an AHU Controller; this is done by putting the AHU Controller into Configuration Mode, and registering the Cascade Module to it. This automatically enables all necessary demand signals, interlocks, etc. to be exchanged between the Controllers across the network, but it will not update the number of stages of heating or cooling in the AHU Controller’s sequence The number of stages of heating and cooling that the AHU Controller has in its sequence are set by 2 Configuration Parameters in the AHU Controller HTSG and CSTG; note that these are not automatically updated when the Cascade Modules are registered, and so must be manually entered using a Zone Controller or SeaChange Doorway.

Up to 2 Cascade Modules may be registered to an AHU Controller.

Configuration

The TYPE parameter determines whether the Cascade will function in Heating or Cooling, this parameter will be set in the factory, Heating is 1, Cooling is 2.

Alarms

The two inputs can be used for status monitoring. If it is required to raise an alarm on status change then this can be acheived by setting ALMD to 1, and setting ALST to the alarm state, 1 is short circuit on the input.

Options and Product Codes

Air Handling Unit Cascade Submodule

CAS / DIN / AHU / [driver option]

Driver options

SC Controls Ltd

PO Box313
Wadhurst
East Sussex
TN5 6JL

phone 08707 606040
fax 08707 606041
e-mail seachange@sccontrols.co.uk
http:// www.seachange.co.uk