Carrier WeatherExpert 50LC 07 Series Installation Instructions Manual

Also see for 50LC 07: Controls, Start-Up, Operation and Troubleshooting Service and maintenance instructions Service and maintenance instructions

24SINGLE POINT BOXES AND SUPPLEMENTARY FUSESWhen the unit MOCP device value exceeds 60-A, unit-mount-ed supplementary fuses are required for each heater circuit.These fuses are included in accessory single point boxes, withpower distribution and fuse blocks. The single point box willbe installed directly under the unit control box, just to the leftof the partition separating the indoor section (with electricheaters) from the outdoor section. The single point box has ahinged access cover. See Fig. 39. The single point box also in-cludes a set of power taps and pigtails to complete the wiringbetween the single point box and the unit’s main control boxterminals. Refer to the accessory heater and single point boxinstallation instructions for details on tap connections or field-installed electric heat accessory.All fuses on 50LC units are 60-A. (Note that all heaters arequalified for use with a 60-A fuse, regardless of actual heaterampacity, so only 60-A fuses are necessary.)Fig. 39 — Typical Single Point InstallationSINGLE POINT BOXES WITHOUT FUSESSome unit heater applications not requiring supplemental fusesrequire a special single point box without any fuses. The acces-sory single point boxes contain a set of power taps and pigtailsto complete the wiring between the single point box and theunit’s main control box terminals. Refer to accessory heaterand single point box installation instructions for details on tapconnections or field-installed electric heat accessory.LOW-VOLTAGE CONTROL CONNECTIONSPull the low-voltage control leads from the heater module(s) -VIO and BRN (two of each if two modules are installed; iden-tify for Module #1) - to the 4-pole terminal board TB4 locatedon the heater bulkhead to the left of Heater #1. Connect theVIO lead from Heater #1 to terminal TB4-1. For 2-stage heat-ing, connect the VIO lead from Heater #2 to terminal TB4-2.For 1-stage heating with 2 heater modules connect the VIOlead from both Heater #1 and #2 to terminal TB4-1. Connectboth BRN leads to terminal TB4-3. See Fig. 40.Fig. 40 — Optional or Accessory Electric HeaterControl ConnectionsHumidi-MiZer® System Control ConnectionsNOTE: It is suggested to ensure the Auto-Changeover function ofan installed thermostat is enabled when used in conjunction withthe Humidi-MiZer Adaptive Dehumidification system.HUMIDI-MIZER SYSTEM – SPACE RH CONTROLLERThe Humidi-MiZer dehumidification system requires a field-supplied and installed space relative humidity control device.This device may be a separate humidistat control (contact clos-es on rise in space RH above control setpoint) or a combinationthermostat-humidistat control device with isolated contact setfor dehumidification control.NOTE: Use of a humidistat device is not permitted on 50LC unitsequipped with RTU Open control; these units require use of afield-supplied RH sensor (33ZCSENSRH-02 or 33ZHCSEN-DRH-02), or a ZS series sensor with humidity sensing. System-Vu™ controls requires a Space Humidistat (HL38MG029), a WallMount Space Humidity Sensor (33ZCSENSRH-01), or a DuctMount Humidity Sensor (33ZCSENDRH-01).To connect the Carrier humidistat (HL38MG029)1. Route the humidistat 2-conductor cable (field-supplied)through the hole provided in the unit corner post.2. Feed wires through the raceway built into the corner post(see Fig. 35) to the 24-v barrier located on the left side ofthe control box. The raceway provides the UL-requiredclearance between high-voltage and low-voltage wiring.3. Use wire nuts to connect humidistat cable to the leads inthe low–voltage wiring (as shown in Fig. 42), connectingPNK to PNK and PNK/BLK to PNK/BLK.NOTE: 50LC**07 units require a 3-stage cooling thermostat de-vice and are not compatible with Carrier’s Edge® Pro thermidistat.Table 3 — Heater Model NumberBARE HEATERMODEL NUMBER C R H E A T E R 0 0 1 A 0 0Heater Sales Package PNO Includes:Bare HeaterCarton and packing materialsInstallation sheetC R H E A T E R 1 0 1 A 0 0ALLIED PAMODEL NO.ERIAL NO.CORP.OD22.23123ISTED AIRNDITIONINGUIP ACCESS346N .P / N 2- 5610-4 REV11 1321 23CONTROLBOXBUSHINGSINGLEPOINT BOXMOUNTINGSCREWSFOAMBUSHINGDRIP BOOTBRACKETMOUNTINGSCREWSHEATERRELAYSPOWERWIRESHEATERMOUNTINGSCREWSINTEGRATEDSTAGINGCONTROL(ICS)BOARD