Fast cooling speed / stable performance / low energy consumption / long life
制造 Specializing in the manufacture of temperature control equipment
15062688501 (same number on WeChat)
Service Hotline: 0512-57781659
Company Address: No. 299 Youbi Road, Kunshan City, Jiangsu Province
Company phone: 0512-57781659
Company Fax: 0512-57781259
Company email: email@example.com
Release time: 2019-06-24 14:31:12
An Shijia Xiao Zhang saw, this is not the startup interface of the thermostat when starting up?
When this problem occurs, the first time I think of it is that the temperature controller has a power outage during operation, and it is the type that flashes over, not the air switch trips.
At this time, I quickly found out the machine's outgoing archive photos on the assistant computer based on the nameplate information taken by the user. The photo shows that this SJ-01AS air-cooled chiller is a thermostatic unit, and the temperature controller is GW531, 60021 model. The chiller thermostat has an auxiliary bypass function, which can adjust the hot gas bypass valve and 3KW electric heating tube in real time according to the set temperature to achieve a constant temperature of plus or minus 1 degree.
After grasping this information, I immediately called the users at the scene and remotely instructed the users to find and eliminate the possible causes one by one.
First let the user check whether the various circuits, electrical appliances and connection terminals are tight, and exclude whether the solenoid valve and electric heating tube are normal. With the cooperation of the user, a set of procedures was performed, but the problem was not found. The chiller thermostat still restarted during the heating and constant temperature. And through the control logic and cooling operation can be very clear, the thermostat itself is no problem. At this point, four hours have elapsed since the problem appeared, and the user has become anxious. In order to solve the problem quickly and deliver the complete set of equipment in a timely manner, we installed the after-sales personnel and rushed to the scene immediately. The user's site was far away in Tieling, Liaoning. After-sales personnel immediately bought the high-speed rail ticket departing on the same day and rushed to it.
At noon the next day, Wu Gong, an after-sales engineer, successfully arrived at the customer's site and immediately started maintenance work.
After completing a set of routine inspections according to procedures, Wu Gong still found no problem. At this time, the experienced Wu Gong suddenly thought that this was a single-phase voltage chiller. In the past after-sales maintenance, various conditions encountered were likely caused by insufficient voltage.
Thinking of this, Wu Gong immediately used the multimeter and began to measure the voltage of the circuit breaker incoming line. The voltage is actually only 156V. I asked the construction staff on site to know that the original distribution box was far away from here, and the wiring of this chiller was pulled from a place 700 to 800 meters away.
The current situation is clear in Wu Gong's eyes. It turns out that the power cable used by the user is a copper cable with a length of 1,000 meters and 1.5 square millimeters. The ultimate reason is that the cable length is too long, the cable cross-sectional area is too small, and the voltage drop is too large. Then the final input chiller voltage is only 156V. This voltage compressor and water pump can work because this voltage is within the allowable deviation range. And the power of the compressor and water pump is very small. When the water temperature inside the water tank of the chiller needs to use electric heating to keep the temperature constant, the solenoid valve and electric heating start to work. The power of the solenoid valve is not large and can be ignored, but the power of the electric heating is 3 KW. So once it starts, it will cause great fluctuations in the voltage of the entire unit, and the voltage of the thermostat will not be enough to cause a flashover phenomenon, which will cause the thermostat to restart.
Here, according to the related problems encountered this time and in the past, I have summarized a few points that need to be noted by the manufacturers of chiller:
Regarding the single-phase voltage chiller, there are some factories that do not have a neutral wire, so the ground wire is used as the neutral wire. This situation will also cause the voltage of the chiller to fail. If the leakage protection switch is installed, this situation is completely Can't turn on the machine.
The length of the power cable cannot be too long. First, it is too long. The price of copper cables is not cheap. If it is a high-power cable, the price is even higher. The second is the problem encountered this time. The excessive voltage drop caused the input voltage not to reach the rated voltage. Even if the chiller can start normally, but the compressor and water pump and the life will be greatly reduced if the chiller runs for a long time under low voltage conditions.