Robertshaw SlimZone Deluxe ZONE CONTROL SYSTEM - Manual (Page 10)

IMPORTANT:
In order to avoid electrical interference to sensitive components, no wiring to the panel
should cross over the panel.
6.6 LOGIC PANEL POWER SUPPLY
The Robertshaw SlimZone Deluxe logic panel requires a separate 24VAC, 40VA transformer.
Never use the equipment transformer or any other transformer used to power other
devices. Refer to the illustration on page 15, Logic Panel Terminal Designation Illustration for
Power – Detail A.
6.7 MOTORIZED ZONE DAMPER POWER SUPPLY
A separate 24VAC transformer must be used to power motorized zone dampers and zone
thermostats. Depending on the total number of zone dampers, multiple transformers may be
used to comply with UL Class II. Each zone terminal has a dedicated 24L and 24N input to
receive 24 Volt power for the damper(s) and zone thermostat. A minimum of 12VA is suffi-
cient for each zone damper. As an example, when using Robertshaw motorized zone
dampers that are rated at 12VA, a single 24VAC, 40VA transformer could be wired in parallel
with up to three zones each having a single zone damper. Refer to the illustration on page
16, Logic Panel Terminal Designation Illustration for Zone – Detail B.
NOTE:
Some installations may require multiple dampers to be used on a single zone. The logic
panel zone damper relays can handle up to five (5) Robertshaw motorized zone dampers for
a total of 60VA per zone.
6.8 MOTORIZED ZONE DAMPER INSTALLATION
Robertshaw motorized zone dampers are designed to work with low pressure systems (1.0
inches wg or less). Balancing dampers should be installed ahead of all zone dampers.
Whenever possible, zone dampers should be installed at least 10 ft (3m) from discharge
grilles and registers. A flex or lined duct is recommended for the last 5 ft (1.5m). The pres-
sure drop across typical control dampers is negligible and normally not a factor when sizing
or calculating branch duct CFM. Robertshaw zone dampers are available in 2-wire, power
close/spring return open or 3-wire, power close/power open configurations. Each zone ter-
minal block has dedicated terminals for either a 2-wire or 3-wire damper input. Refer to the
illustration on page 16, Logic Panel Terminal Designation Illustration for Zone – Detail B.
6.9 BYPASS DAMPER INSTALLATION
In order to maintain constant design static pressure, a bypass system is highly recommend-
ed. In some 2 zone applications, a bypass damper may not be required providing that each
zone can be oversized to handle 75% of the total system CFM.
In applications where the equipment cooling tonnage is 5 tons or less, a Robertshaw baro-
metric bypass damper can be applied.
In applications where the equipment cooling tonnage exceeds 5 tons, a motorized bypass
damper and static pressure control must be incorporated.
SlimZone Deluxe
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