Master Control Panel
Master Control Panel
Master Control Panel
Master Control Panel
Master Control Panel
HEATER CONTROL SYSTEM
The System shall be a PACE DDC Perimeter Electric Heat Control
System. The control system shall provide automatic continuously
modulated heat output from the perimeter electric heating system.
This system shall use outdoor parameter sensing to establish the
system operating point. System designs which include interior
sensing shall not be acceptable. The heating system output shall
vary inversely with the change in outdoor temperature with 0%
output at 60OF and 100% output at building design outside temperature.
The system shall proportionately compensate for building service
voltage reductions by accurately maintaining heater BTU output.
The system shall also automatically adjust heater output to compensate
for wind and rain.
System shall be an all state-of-the-art Microprocessor-based design
using digital control modules and an Interface Module for maximum
reliability and fast response. System shall include a communications
module to allow remote monitoring and changing of the parameters
of System characteristics to meet the specific building characteristics
over the normal range of operation.
The Control Configuration and sequences shall include:
1. Night Setback, demand limited.
2. Demand limited Morning Pickup with averaged interior temperature
3. Solar reset Zones.
4. PACE Morning Pickup RTU/AHU Control Sequence
5. Communications Package (Requires Telephone Line by
Night Setback, Demand Limited: A night setback feature shall be
provided to reduce system output during unoccupied time periods.
This option shall not cause any abnormal electrical peak demand
as monitored by the utility during the change from day to night
operation or from night to day operation.
Morning Pickup, Demand Limited: A demand limited morning pickup
feature shall be provided which
will begin at the end of the night setback period and shall have
an optimized start schedule by a micro
block function in accordance with interior temperature averaged
from difference locations. The
percentage limit of morning pickup shall be easily adjusted from
0 to 50% of total system output. This
function shall also include a night setback override which will
prevent night setback when outside
conditions require system operation above 70% output, thus insuring
that there will be sufficient system
reserve capacity for morning pickup.
Solar Reset: The control system shall include an individually
adjustable solar setback zone(s) of
the building exposures. This option shall allow the system to
automatically reset each exposure
to a lower operating percentage of heat output depending on solar
heat gain. The percentage of
solar setback shall be easily adjustable from 0% to 100% of total
system output. The solar sensors shall
be of the angular responsive type to provide a solar signal proportional
to the magnitude of the actual
solar radiation including the variation due to the angle of incidence
to the plane of the wall comprising
the solar zone.
Pickup RTU/AHU FAN CONTROL Sequence: This control function shall
send a LAN Broadcast (Alternate: a signal-24VAC or Dry Contact)
to turn on RTU/AHU Fan(s) for improved temperature measurement
and to distribute the morning warmup heat. The unit(s) shall remain
in recirculation mode without cooling.
Zone Tracking: This control function block shall provide Zone
Tracking for auxiliary zones. This
option shall allow adjustment of the 100% control signal value
for auxiliary slave SCRs) without affecting
the 0% control signal. This option shall be independent of the
main system calibration controls for 0%
and 100% operating points.
Override Relays: Individual override relays shall be provided
for override Zones. These override
relays when powered by the control module(s) or the manual override
timers, if provided, will bring
these Zone(s) back to day operation without causing any abnormal
MASTER CONTROL PANEL:
The Master Control Panel shall be a state-of-the-art Microprocessor-based
design using DDC control modules. The Master Control Panel shall
be completely pre-wired and tested. The control module(s) shall
be loaded with the required Software to operate the system to
meet the building design criteria. The communications module shall
allow to change the parameters of System characteristics over
the telephone line.
SENSORS: The outdoor ambient sensors (active 8, passive) are to
be located on the north or northwest side of the building in such
a manner as to prevent the sun from striking sensor(s) during
any part of the day all year around. Sun shields are to be provided
The solar sensor(s), interior mounted (or outdoor mounted), are
to be located on each solar exposure with the sensor parallel
to the building face. The height of the sensor shall be so as
to respond to the average solar load, especially during sunrise
The outdoor ambient sensors (active & passive) and outdoor
solar sensor(s) shall be mounted on the building in a secure and
safe location. All outdoor sensors shall be located a minimum
of 10 feet from the ground level and in the open away from closed,
blocked, or restricted areas and/or as shown on the architectural
drawings. Alternate sensor locations must be verified.
The Morning Pickup sensors are to be located away from any sources
of heat and approximately 5 feet from floor level.
CONTROL WIRING: The sensor control wiring shall consist of a twisted
pair (or twisted three-wire) where indicated on the field control
wiring drawings. The sensor control wiring
MUST be run separate from any power wiring or any other
control wiring. All PACE sensor control wiring can be run together.
Shielding is required for mechanical protection only. Wire is
to be supplied by electrical contractor. Wire gauge shall be in
accordance with GEEI drawing 091-21-01.
Modular Type SCR Power Controllers: The Modular Power Controller(s)
(MPC) shall be a completely prewired U.L. Listed assembly. The
SCR (Silicon Controlled Rectifier) assembly shall be mounted in
a ventilated enclosure with individual "Power On" 8, "Load On"
lights for each circuit. The complete unit shall be U.L. Listed.
The SCR device shall be of a plug-in design for simple field replacement.
Standard Type SCR Power Controllers: The SCR (Silicon Controlled
Rectifier) Power Controllers shall be completely prewired and
include a U.L. Recognized SCR assembly consisting of SCR heat
sink assemblies, timing circuit, a "phase correct" indicator,
12T fusing and necessary line and load terminal blocks. Auxiliary
power terminals shall also be provided for initial testing circuits
and as emergency bypass lugs. This SCR assembly shall be mounted
in a ventilated enclosure with individual phase "load on" lights.
SCR Power Controller MUST operate independently and randomly from
the control signal received from the Master Control Panel.
The SCR control timing circuit shall be of the zero crossover
switching type so as not to produce any radio frequency interference
(RFI) and shall have an internal feedback circuit for stability.
The control timing circuit shall be designed so as to minimize
the possibility of any visible light flicker within the building.
The control timing circuit shall turn power off if the control
signal is lost. The SCR heatsink subassemblies shall utilize standard
SCR devices for reliability and shall have an ambient operating
temperature of at least 1220F. Triac devices shall not be acceptable.
MDR TYPE POWER CONTROLLER(S):
The MDR Power Controllers as assembled by Harrison Electro Mechanical
Corporation, a wholly-owned subsidiary of General Electronic Enterprises,
Inc., shall be a completely prewired U.L. Listed assembly. This
power controller assembly shall include U.L. and/or C.S.A. approved
35 Amp mercury displacement type relays (MDR) of a hermetically
sealed type construction, necessary zone driver circuits, necessary
tagged line load terminals and control terminals.
Each Power Controller timing circuit(s) shall be calibrated to
operate from the control signal with less than a +/-2% output
error relative to 100% output over the input control signal range
of 5% to 95%. These accuracies must be readily obtained during
extreme building voltage variations. Demonstration of these accuracies
MUST be provided.
The Master Power Controller(s), when supplied, shall provide a
building voltage monitor signal to the Master Control Panel.
The Power Controllers shall be rated as listed in the equipment
WARRANTY: A parts warranty shall be provided on all equipment
supplied which will extend for a period of 12 months from system
Startup, Date. In the event System Startup has not occurred within
6 months of Equipment Shipment Date; the warranty period shall
be for a period not to exceed 18 months from Equipment Shipment
Date. When provided, MDR Type Power Controllers shall have an
additional 2year extended parts warranty on the individual relays.
SERVICE: Field installation supervision,
preliminary system checkout and field start-up calibration shall
be provided. A second field calibration verification shall be
provided within the first year of operation.
One year's Extended Warranty Service labor shall be provided to
maintain the proper operation of the supplied equipment for one
year after date of system startup. Service calls not
specifically the result of system malfunction are not included.
As minor field readjustments can reduce energy waste, a one-year
consulting service will be provided to allow the building maintenance
personnel to tailor calibration adjustments to the actual building
characteristics, thus allowing for maximum energy savings.
OPERATION: Due to the complex function
of the PACE System and interaction of the PACE System with building
characteristics, initial start-up and system operation will be
delayed until sufficient building occupancy is available for successful
system operation. The heating system will be fully functional
by use of the SCR auxiliary lugs but without system control.
ELECTRICAL CONSIDERATION: The
SCR Power Controller(s)
SHALL NOT be operated in the load circuit until a full
power check has been made to verify that a "no-short" condition
exists at full voltage for each heater sub-circuit.
All loads, including the field power wiring,
MUST be operated at full rated voltage and current prior
to the SCR power controller(s) to verity a no-short condition.
The SCR power controller(s) warranty will be void if the SCR's
are operated into a shorted load. Temporary operation of SCR Power
Controllers prior to system startup is NOT allowed and may void
The Standard type SCR power controller(s)
MUST be electrically supplied using conservatively rated
feeders to minimize any feeder voltage drop. The Standard type
SCR power controller feeders over 100 Amps must be connected directly
from the main building distribution system. The Standard type
SCR power controller feeders must not be common to any lighting
circuits. The Standard type SCR power controller maximum load
ampere rating must not be exceeded on any phase. Auxiliary terminals
are provided for initial testing of heaters and services.
All SCR power controller load calculations must be made at the
"nominal" supply voltage. The loads must be restrictive for proper
SCR power controller operation. Motors of lights
MUST NOT be connected to the load side of the SCR power
controller. The circuit breaker(s) feeding a SCR Power Controller
MUST NOT exceed the rating specified for that SCR power
The SCR power controller room ambient during full load operation
must not exceed 1050F. SCR power controller enclosure must be
mounted in free air for proper ventilation. Each SCR power controller
assembly must be protected from contaminiation such as water,
dust and dirt especially during initial installation.
APPROVALS: Alternate manufacturers
must secure approval prior to bid date. Approval will require
submission of proof of compliance to system specification, proof
of successful total system responsibility and proof of system
operation for installations of a similar design concept which
have been installed and operating for more than three years.