We provide a package solutions for small and medium-sized OEMs and non-standard systems, including electronic expansion valves(EEVs), EEV controllers, pressure transmitters and temperature sensors. This solution has significant advantages in replacing thermostatic expansion valves(TXVs) or capillary, especially in systems with big load changes. The wider adjustment range and faster response speed of EEVs ensure better matching between the desired refrigerant injected into the evaporator and the actual load.
Since the launch of the SEC controller by Sanhua, the cumulative application has been more than 150,000 sets.
The pressure transmitter is installed at the outlet of the evaporator to sense the evaporating pressure (Pe) and convert it into the saturated evaporating temperature (Te). The temperature sensor is also installed at the outlet of the evaporator and near the pressure transmitter, used to sense the temperature at the outlet of the evaporator (overheating state Ts). The Sanhua SEC controller calculates the superheat (SH = Ts - Te) based on the collected temperature and pressure signals, and compares it with the target superheat to determine the action of the EEV. The Sanhua SEC controller uses an advanced PID algorithm to precisely control the superheat at the outlet of the evaporator.
"Heavy Duty" Controller: Fearless in cold and ensure the Food Safety
Due to the inability of the above-mentioned SEC controller to be installed in the low-temperature room, the difficulty of wiring increases significantly when the controller needs to be installed in a remote room. Therefore, Sanhua specifically upgraded the EEV controller for cold storage applications and launched the " Heavy Duty " series.
Chinese name of "Han Wei" is a homophone of "Heavy" in its English name "Heavy Duty" and means Guard in Cold. As the name suggests, the" Heavy Duty" controller can work in low-temperature environments and can be directly installed in a warehouse with a temperature of -35 ℃.
The two most concerned aspects of such a controller are low temperature and water resistance. We have a rigorous design for this. All components are selected at -40 ℃ or even lower, and the controller's wires and housing are sealed with epoxy. The waterproof rating of "Heavy Duty" is far better than IP67.
The product has passed a long-term operation test of 3 months, accompanied by-40 ℃ to 60 ℃ of temperature alternation, and high temperatures above 95% during operation. The product has passed the EMC electronic compatibility test and can work well with motor fans.
"Heavy Duty" has 4 models: SEC611-HD,SEC621-HD, SEC631-HD and SEC641-HD, where HD stands for Heavy Duty.
- SEC611-HD and SEC631-HD have integrated coils, with a coil wire length of 60cm, which cannot be replaced.
- SEC621-HD and SEC641-HD have detachable coils, connected through waterproof connectors, which can be replaced and purchased separately, with a total wire length of 2m.
- Among them, SEC631-HD and SEC641-HD are mainly for CO2 and HC and you need to order the pressure sensor separately.
- From the perspective of wire length, the 60cm coil of the expansion valve is sufficient for users of air cooler with SEC611-HD. For other evaportors in a cold storage, you need to find the nearest wall inside the room. In this case you can choose SEC621-HD, which has a 2m coil length (EEV coil).
- You may need a remote display and parameter copy device, respectively name as MD03 and MD04.
- The waterproof coil can be purchased separately and used in conjunction with SEC621-HD.
- Pressure transmitters can also be purchased separately. This model is specially designed with a range of -1 to 20 bar for SEC611-HD and SEC621-HD, and 1 to 60 bar for SEC631-HD and SEC641-HD in case you use CO2 as refrigerant. Other models can be purchased, but ensure the sensor output is 0.5V-3.5V or else it cannot be matched. For HC it is recommended to choose a model with solder connection.
- Although the temperature sensor is integrated with the controller, if after-sales replacement is indeed needed, you can purchase a separate NTC temperature sensor (the same as SEC611) and connect it by cutting off the original temperature probe and replacing it.
- Please note that the packaging of the SEC611-HD or SEC621-HD controller includes the controller, coil, pressure transmitter, and temperature sensor. You only need to choose a valve body. For SEC631-HD and SEC641-HD, you need to order pressure transmitter separately.
