External Time Clock - Daikin RoofPak RPS Series Installation And Maintenance Manual

External Time Clock

You can use an external time clock as an alternative to (or in
addition to) the MicroTech III controller's internal scheduling
function. The external timing mechanism is set up to open
and close the circuit between field terminals 101 and 102.
When the circuit is open, power is not supplied to binary input
MCB-BI1. This is the normal condition where the controller
follows the programmable internal schedule. When the circuit
is closed, power is fed to BI1. The MicroTech III controller
responds by placing the unit in the occupied mode, overriding
any set internal schedule.
For more information, see the "Digital Inputs" section of
"MicroTech III Applied Rooftop Unit Controller."
Figure 99: External Time Clock or Tenant Schematic
IM 926-3 • ROOFPAK APPLIED SYSTEMS
External Time Clock or Tenant Override
There are several methods of switching the rooftop unit
between occupied and unoccupied operation. It can be done
by the controller internal schedule, a network schedule, an
external time clock, or a tenant override switch.
If the internal schedule or a network schedule is used, field
wiring is not required.
An external time clock or a tenant override switch can be used
by installing a set of dry contacts across terminals 101 and 102
IM 696,
on the field terminal block (TB2). When these contacts close,
24 V (AC) is applied to binary input MCB-DI3, overriding any
internal or network schedule and placing the unit into occupied
operation (provided the unit is not manually disabled). When
the contacts open (24 V (AC) is removed from MCB-DI3) the
unit acts according to the controller internal time schedule or a
network schedule. Refer to the unit wiring diagrams for specific
wiring termination details.
86
Unit Options
www.DaikinApplied.com