Chapter 3 - 6 Installing VO2 Analog Output Boards - icemeister.net

Chapter 3 - 6VO2 Description andIdentificationInstalling VO2 Analog Output BoardsThe VO2 Variable Output board provides an AKC 55 system with 2 variable outputs for control ofloads like variable speed compressors and variable speed condenser fan motors. Each output can supply0-10 VDC or 0-5 VDC. Both outputs can supply the same range or there can be one in each voltagerange.Since they are nodes on the I/O network,VO2 boards communicate with a host AKC55 over TP-78K twisted pair shielded cable.The board’s name and version number areprinted on the board as shown in thefollowing illustration.MountingThe VO2 board is designed for 3" snaptrack mounting in either a Danfoss IO4R or IO12 enclosure, andOEM control panel, or other enclosed spaces. Snaptrack for I/O boards can be mounted on any flatsurface where codes and good electrical practice permit. A Danfoss IOPS-series power supply must beused to provide operating voltage for I/O boards not mounted in a Danfoss IO4R or IO12 enclosure.Addressing a VO2Each of the VO2 boards connected to an AKC 55 must have a unique address in the range 01-99. Theaddress is set by the two rotary switches located side-by-side beneath the board’s “status” and “service”LED’s. Each switch has an arrow pointer which serves also as a screwdriver slot. Use a small screwdriverto rotate the arrowhead on each switch until the left arrowhead points to the first digit, and theright arrowhead to the second digit, of the correct address.AKCESS System Manual RC.IU.B1.22 4/99.1 3-25

Inspection of theInstalled VO2When a VO2 Variable Output Board is ready for operation, you should be able to observe the following,proceeding clockwise around the board from the power terminal strip:1. Power (12 VAC or 15 VDC) has been connected to the “12 VAC” terminal strip.2. The status LED should be blinking. If the status LED is off, there is no power to the board(check the fuses). If the status LED is constantly on (not blinking), the board is not communicatingwith its AKC 55. Make sure the AKC 55 has been configured for this board; ifconfigured, there will be information in at least one of the Board and Points screens; you caninvestigate, and supply configuration information, if necessary, by following the proceduresdescribed in Section IV of this manual.3. The service LED will normally blink briefly when the network is scanned, but if the serviceLED remains steadily on, the VO2 board is defective and should be replaced.4. The address switches have been set to a valid address.5. Loads are connected to one or both of the pair of output terminals.6. Connection has been made to the I/O network of an AKC 55 at the “NETWORK” terminal.7. If this board is the last node on a run, make sure that it is terminated by using one of theterminators supplied with the AKC 55.AKCESS System Manual RC.IU.B1.22 4/99.1 3-27

Chapter 3 - 7RTC DescriptionAvailabilityCapabilities andCapacitiesCapacity:Sensor InputsInstalling RTC Rooftop ControllersThe RTC Rooftop Controller can operate in two modes: as a node in an AKCESS I/O Identification network,connected to an AKC 55, or as a stand-alone rooftop controller. The RTC communicates over theI/O network when it is a node in an AKCESS system. Like an AKCESS Smart Case Controller, theRTC is an intelligent controller. If communications are interrupted or lost, the RTC will continue tooperate as a stand-alone controller with the same strategy and settings as selected during its configurationas part of the AKCESS network.The RTC is available from Danfoss in a rainproof enclosure or without enclosure for installation byoriginal equipment manufacturers.There can be as many as 32 RTC rooftop controller nodes in an AKCESS system, as long as the totalnumber of HVAC systems does not exceed 32.The RTC has one required and up to seven optional sensor inputs, which are pre-assigned for use asfollows:InputNumberSensor1 Zone Humidity 12 Zone Humidity 23 Outside Humidity4 Zone Temperature 15 Zone Temperature 26 Outside Temperature7 Supply Temperature8 Return TemperatureThese sensor inputs need not be wired directly to the RTC board; they can be set up during configurationto be received from sensors connected to any SI board in the AKCESS system.Required SensorCapacity:On/Off inputsAt least one zone temperature sensor or the return temperature sensor must be connected in order for theRTC to function.There are up to four optional on/off inputs, pre-assigned for use as follwos:InputNumber1 Fan2 Cooling 1On/Off Input3 Heating 1 OR Cooling 24 Smoke Detector OR Differential PressureThese on/off inputs can be wired directly to the RTC board or they can be received from any OI boardon the AKCESS network.3-28 System Manual RC.IU.B1.22 4/99.1 AKCESS

Capacity:Relay OutputsRelay outputs are provided for control of HVAC devices, and are pre-assigned for control as follows:Relay Output NumberControlled Device1 Fan2 Damper3 Cooling, Stage 14 Cooling, Stage 25 Cooling, Stage 36 Heating, Stage 17 Heating, Stage 28 Heating, Stage 3MountingAddressingUsing the pre-drilled holes, mount the RTC securely to a solid surface. Operating temperature must bein the range from 0 o F to 130 o F at 90% rh (non-condensing) or from 0 o F to 122 o F at 95% rh (noncondensing).The RTC is addressed by setting the two side-by-side rotary switches on the circuit board. Each RTCmust have a unique address in the range 01-99. Each switch has an arrow pointer which serves also as ascrewdriver slot. Use a small screwdriver to rotate the arrowhead on each switch until the left arrowheadpoints to the first digit, and the right arrowhead to the second digit of the correct address.AKCESS System Manual RC.IU.B1.22 4/99.1 3-29

Network ConnectionsThe RTC is connected to the I/O network at the terminal strip labeled “NETWORK”. When connectingfrom board to board (point-to-point or “daisy-chain” wiring), use only twisted- pair cable meeting thespecifications given in the illustration below. There is no polarity to observe; connect the two signalwires to the terminals labeled “A” and “B”, and the cable shield to the terminal labeled “shield”.If your RTC is atthe end of a maincable run, it has tobe terminated !!.Sensor ConnectionsUp to 8 sensors can be connected to an RTC board. The board has three sets of terminals for humiditysensors and five sets for temperature sensors. Each set of terminals is dedicated and labeled for aparticular sensor. Although sensor leads can be up to 1000' long, when leads are over 100', take care tocalibrate and offset sensor readings (see Chapter 5 section 2 and use the Sensor Adjustment screenselected from the appropriate Service menu).Connect temperature sensor to GND and SIG terminals as shown in the following illustration; there is nopolarity requirement:3-30 System Manual RC.IU.B1.22 4/99.1 AKCESS

ConnectinggOn/Off InputsThe RTC has four sets of terminals for on/off inputs. Each set of terminals is labeled with the name ofthe device for which the terminals are intended.ConnectingRelay OutputsControlled loads are connected to their RTC terminals by wiring to the common and either the normallyopen (“NO”) or normally closed (“NC”) screw terminals labeled for the particular load.RTC PowerConnectionsInspection of theInstalled RTCPower connections (24 VAC, +10% / -15%) are made to the terminals labeled “24 VAC.”When an RTC Rooftop Controller is ready for operation, you should be able to observe the following,proceeding clockwise around the board from the power terminal strip:1. Power connections (24 VAC) have been made to the “24 VAC” terminal.2. Controlled loads are connected to the relay output terminal strips (labeled C, NO, and NC forCommon, Normally Open, and Normally Closed) for Fan, Damper, Cool 1, etc.3. Loads to be monitored are connected to the on/off input terminals (labeled N and L for Neutraland Line) for appropriate devices.4. Connection has been made to the I/O network of an AKC 55 at the “NETWORK” terminals.5. Sensor connections have been made to the terminal strips labeled for Zone Humidity, OutsideHumidity, Zone Temperature, etc. For temperature sensors, only SIG and GND connectionshave been made, and for humidity sensors, 12V, SIG, and GND have been connected.6. The Service LED will normally blink briefly when the network is scanned, but if the serviceLED remains steadily on, or blinks constantly, the RTC board is defective and should bereplaced.7. If this board is the last node on a run, make sure that it is terminated by using one of theterminators supplied with the AKC 55.AKCESS System Manual RC.IU.B1.22 4/99.1 3-31