The Pelican Pearl controller allows you to take over an RTU (rooftop unit) and be able to control the economizer. Given we use a TC3 or TC4 thermostat we can also do demand ventilation based on CO2. There are uses for this where we can also just monitor temperatures or alarm contacts. Let us know what you want to do and we will help you out. Also this allows a 3 wire connection between a RTU and the thermostat and still have full functionality.

Here is information on Pelican Pearl and the Pearl expansion module.  We have provided data sheets and install manuals. There is also a sequence of operations document as well.

| PEARL Inputs and Outputs

MODULATING OUTPUTS:

(A1, A2) 0 - 10 VDC Signals

Two modulating outputs that are most commonly used for outside damper, variable speed fan, and/or modulating temperature control.

ENABLE OUTPUT:

(E) Terminal

During an economizer or demand ventilation cycle, this outputs 24 VAC to turn on exhaust fans or open dampers.​

ANALOG INPUT:

(S1, S2) 0 - 10 VDC Signal

When used as an outside air damper controller, the PEARL accepts a feedback signal to confirm the outside damper is in the correct position.​

EXTERNAL INPUTS:

(T1, T2, T3) 10K Type II or Dry-Contact

Pull in up to three external temperatures. Most commonly an HVAC unit's discharge, return, and/or outside air temperatures. Or connect a dry-contact into the PEARL to incorporate a third-party occupancy sensor or equipment alarm.

CONNECTION TO THERMOSTAT:

(R, C, D) 3-Wires Only

The PEARL and its Pelican thermostat communicate over a three wire connection.
R: 24 VAC, C: Common, D: Data.

DIGITAL OUTPUT:

(Y, Y2, W, W2, G) HVAC Unit Control

Remove the wiring module from of your Pelican thermostat and mount it into the PEARL. The PEARL will enable your HVAC equipment's heating, cooling, and fan stages.

SYSTEM PROTECTIONS:

Mixed air low limit safety.
Free cooling enable/available indication.
Economizer enabled indication.
Compressor enabled indication.
Heating enabled indication.
Temperature sensor readings.
Minimum outside damper setting.
Maximum outside damper setting.
Outside Compressor Lock-Out
Temper Low Ambient Air