General Information

Base Loading Control

Algorithm:

This feature allows an external controller to directly modulate the capacity of the chiller. It is typically used in applications where virtually infinite sources of evaporator load and condenser capacity are available and it is desirable to control the loading of the chiller. Two examples are industrial process applications and cogeneration plants. Industrial process applications might use this feature to impose a specific load on the facility’s elecrical system. Cogeneration plants might use this feature to balance the system’s heating, cooling and electrical generation.

All chiller safeties and adaptive control functions are in full effect when Base Loading control is enabled. If the chiller approaches full current, the evaporator temperature drops too low, or the condenser pressure rises too high, Tracer CH530 Adaptive Control logic limits the loading of the chiller to prevent the chiller from shutting down on a safety limit. These limits may prevent the chiller from reaching the load requested by the Base Loading signal.

Base Loading Control is basically a variation of the current limit algorithm. During base loading, the leaving water control algorithm provides a load command every 5 seconds. The current limit routine may limit the loading when the current is below setpoint. When the current is within the deadband of the setpoint the current limit algorithm holds against this loading command.

If the current exceeds the setpoint, the current limit algorithm unloads. The “Capacity Limited By High Current” message normally displayed while the current limit routine is active is suppressed while base loading.

Base loading can occur via Tracer, External signal, or front panel.

Tracer Base Loading: Current Setpoint Range:

(20 - 100) percent RLA

Requires Tracer and Optional Tracer Communications Module (LLID)

The Tracer commands the chiller to enter the base load mode by sending the base load mode request. If the chiller is not running, it will start regardless of the differential to start (either chilled water or hot water). If the chiller is already running, it will continue to run regardless of the differential to stop (either chilled water or hot water), using the base load control algorithm. While the unit is running in base loading, it will report that status back to the Tracer by setting “Base Load Status = true” in the Tracer Status Byte. When the Tracer removes the base load mode request (sets the bit to 0). The unit will continue to run, using the normal chilled or hot water control algorithm, and will turn off, only when the differential to stop has been satisfied.

External Base Loading: Current Setpoint Range: (20 - 100) percent RLA

The UCP accepts 2 inputs to work with external base loading. The binary input is at 1A18 Terminals J2-1 and J2-2 (Ground) which acts as a switch closure input to enter the base-loading mode. The second

input, an analog input, is at 1A17 terminals J2 – 1 and 3 (Ground) which sets the external base loading setpoint, and can be controlled by either a 2-10Vdc or 4-20ma Signal. At startup the input type is configured. The graphs in Figure 13 show the relationship between input and percent RLA. While in base loading the active current limit setpoint is set to the Tracer or external base load setpoint, providing that the base load setpoint is not equal to 0 (or out of range). If it is out of range, the front panel current limit setpoint is used. During base loading, all limits are enforced with the exception of current limit. The human interface displays the message “Unit is Running Base Loaded”. Hot Gas Bypass is not run during base loading. If base loading and ice making are commanded simultaneously, ice making takes precedence.

An alternative and less radical approach to Base Loading indirectly controls chiller capacity. Artifically load the chiller by setting the chilled water setpoint lower than it is capable of achieving. Then, modify the chiller’s load by adjusting the current limit setpoint. This method provides greater safety and control stability in the operation of the chiller because it has the advantage of leaving the chilled water temperature control logic in effect. The chilled water temperature control logic responds quicker to dramatic system changes, and can limit the chiller loading prior to reaching an Adaptive Control limit point.

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Trane CVHE-SVU01E-ENX39640712050 manual Base Loading Control Algorithm, 20 100 percent RLA
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CVHE-SVU01E-ENX39640712050 specifications

The Trane CVHE-SVU01E-ENX39640712050 is a high-efficiency centrifugal chiller designed for commercial and industrial applications. This state-of-the-art unit is engineered to provide reliable cooling performance, energy efficiency, and optimized operational flexibility. It is particularly suitable for large-scale facilities that require significant cooling capacity and robust performance under varying load conditions.

One of the most notable features of the CVHE-SVU01E series is its advanced variable speed drive technology. This technology enables the chiller to adjust its speed according to the cooling demands of the facility, resulting in substantial energy savings. By operating at optimal speeds, this unit reduces power consumption and enhances overall efficiency. This is noteworthy in the context of rising energy costs and increasing sustainability demands across various industries.

Moreover, the CVHE-SVU01E is equipped with Trane’s proprietary Compliant Scroll compressor technology. This innovative compressor design minimizes mechanical losses and increases the efficiency of the chiller system. Additionally, the compressor is specifically designed to handle varying refrigerant flow rates, allowing the chiller to maintain performance even when faced with fluctuating conditions.

Another significant characteristic of this chiller model is its use of environmentally friendly refrigerants, aligning with global regulations aimed at reducing greenhouse gas emissions. This commitment to sustainability ensures that the CVHE-SVU01E not only provides excellent cooling performance but also adheres to contemporary environmental standards.

The unit utilizes an advanced control system that simplifies operation and enhances troubleshooting capabilities. The intuitive interface allows facility managers to monitor performance metrics, optimize operation schedules, and conduct remote diagnostics, significantly reducing costly downtime and maintenance efforts.

Furthermore, the compact and modular design of the CVHE-SVU01E makes it easy to install in various settings. Its durability is ensured through the use of high-quality materials and components, designed to withstand the rigors of demanding environments. With reduced maintenance requirements, facility operators can focus on core business functions without frequent interruptions.

In summary, the Trane CVHE-SVU01E-ENX39640712050 combines cutting-edge technologies and features to deliver exceptional performance, efficiency, and reliability in commercial cooling applications. Its advanced design contributes to reduced energy costs, minimal environmental impact, and greater operational flexibility, making it an excellent choice for organizations seeking sustainable and efficient cooling solutions.
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