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Advanced Controls

Advanced Controls of a Kathabar system can be tailored to meet the required scale of the project. These control schemes can vary between to components of different elevation to multiple conditioners utilizing a common regenerator. Of these control schemes there are two common forms of advanced controls: Pump In, Pump Out (PIPO) and Pump, In Pump Out (PIPO) with Gravity Equalize.

Pump In, Pump Out (PIPO) is a typical control method found on systems with components at varying elevations to systems with multiple conditions with a common regenerator. The basis of this design is to control level throughout the entire system. This is done by fixing the strong solution transfer from the regenerator to the conditioner(s). The level in the conditioners is maintained by varying the weak solution return to the regenerator(s). Optional transfer interchanger (economizer) is available for this type of system control to further increase energy efficiency. See the below figure and table for further clarification.

Advanced Controls

BT 1 &2
Bubbler Tube
Used in conjunction with the LCP/ECP to pneumatically sense solution level

FM Flow Meter- Measures and controls the transfer of concentrated solution from the regenerator to the conditioner
LCP/ECP
1
Level & Electrical Control Panel – Provides:

- High level, low level alarms
- Modulating control of V4 based on BT 1 to maintain level
- Motor starters & contactors

LCP/ECP
2
Level & Electrical Control Panel (PLC) – Provides:

- High level, low level alarms
- Water make-up V5
- Modulating control of V3 based on TT leaving air set-point
- Modulating control of KV7 based on BT 2 to maintain level
- Motor starters & contactors

KV7 Conditioner pump out valve – Receives a modulating signal from LCP/ECP 2 to maintain BT 2 set-point
TT Temperature Transmitter- Senses leaving air temperature and transmits the signal to the PLC in LCP/ECP 2 for V3 modulation control to maintain set-point
V3 Conditioner Solution Cooler Valve – Receives a modulating signal from the PLC in ECP/LCP 2 based on TT set-point
V4 Regenerator Heater Valve – Receives a modulating signal from the PLC in ECP/LCP 1 to maintain BT 1 set-point

V5 Water Make-Up Valve – Receives a on/off signal from the PLC in ECP/LCP 2 based on BT 2 low level set-point

Pump In, Pump Out (PIPO) with Gravity Equalize is a typical control method used for systems at the same elevation and which take advantage of an interchanger (economizer). This works by fixing transfer though a plate and frame heat exchanger (interchanger) that is between both the conditioner and regenerator with an additional line to make up the additional transfer due to moisture load variation. Like the basic “pump-in, gravity equalize” control scheme, this system only requires one level control at either the conditioner or regenerator. See the below figure for further clarification.

Advanced Controls

BT Bubbler Tube – Used in conjunction with the LCP/ECP to pneumatically sense solution level

FM Flow Meter- Measures and controls the transfer of concentrated solution from the regenerator to the conditioner
LCP/ECP Level & Electrical Control Panel (PLC)- Provides:

- High level, low level alarms
- Water make-up V5
- Modulating control of V3 based on TT leaving air set-point
- Modulating control of V4 based on BT to maintain level
- Motor starters & contactors

TT Temperature Transmitter- Senses leaving air temperature and transmits the signal to the PLC in LCP/ECP for V3 modulation control to maintain set-point
V3 Conditioner Solution Cooler Valve- Receives a modulating signal from the PLC in ECP/LCP based on TT set-point

V4 Regenerator Heater Valve- Receives a modulating signal from the PLC in ECP/LCP to maintain BT set-point

V5 Water Make-Up Valve- Receives a on/off signal from the PLC in ECP/LCP based on BT low level set-point

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