Is there a difference between a transformer respirator and a moisture absorber?
Date: November 5, 2025 12:23:56
Transformer breather and moisture absorber are different specialized designations for the same equipment, both of which are core protection accessories for oil-immersed transformers.
Transformer breather (moisture absorber) is fixedly installed above the transformer oil pillow and connected to the inside of the oil pillow through a special sealing pipeline to ensure the sealing of the air flow path.
Its typical structure consists of three parts: the transparent desiccant chamber (used to load the moisture absorber), the oil cup (oil seal) at the bottom, and the special connecting pipe to connect the oil pillow, and all the parts work together to realize the protection function.
When the oil temperature is lowered, the oil volume contraction so that the oil pillow to form a negative pressure, the external air filtered by the oil cup impurities, through the desiccant to remove moisture, dry air and then enter the oil pillow; oil temperature increases, the oil volume expansion leads to oil pillow pressure rise, the internal air filtered by the desiccant after the second time, discharged through the cup of the equipment outside.
The most core function is moisture absorption, moisture absorption into the air, to prevent the transformer oil insulation strength decline; at the same time to achieve pressure balance, to avoid temperature changes triggered by pressure fluctuations damage to the equipment; also through the synergistic effect of the oil cup and the desiccant, filtering impurities into the air, to achieve air purification.
Color-changing silica gel is blue when it is not hygroscopic, and changes to pink or white when it is saturated with hygroscopicity; through the combination of physical adsorption and chemical adsorption, it can dry the incoming air to below the dew point of -40℃, ensuring that the air dryness is up to the standard.
The oil level of transformer oil in the oil cup is standardized to be no more than the exhalation nozzle and does not overflow, and should be maintained in the position of the warning line marked in the oil cup; its role is to isolate the external air directly into the respirator, while filtering impurities and dust in the air, double safeguard to enter the cleanliness of the air in the oil pillow.
Silicone replacement must meet one of three conditions: more than 2/3 of the pink area, 12-24 months of use (shorter intervals are required for harsh humid environments), and adsorption saturation of 80% of the rated adsorption capacity.
Before replacement, it is necessary to apply for power outage or adjust the protection device, and change the signal of heavy gas protection; after removing the breather, use dry and clean towel to block the oil pillow interface to prevent impurities from entering; after pouring out the invalid silica gel and cleaning the inner cavity, load 3-5mm specifications of new silica gel, and control the filling amount in the space reserved for expansion at 1/5-1/6 from the top; and at the same time, change the oil in the oil cup of the transformer oil (it is recommended to change it at least once a year). At the same time, replace the transformer oil in the oil cup (it is recommended to replace it at least once a year); after the installation is completed, check the sealing, restore the protection device and observe the operation status of the equipment.
Silicone discoloration is mainly caused by three factors: high ambient humidity, leakage of breather sealing parts, lack of oil in the oil cup; treatment is to improve the ventilation conditions around the equipment, check the sealing parts and replace the damaged parts, and replenish or replace the transformer oil in the oil cup in time.
Breather clogging will lead to gas relay alarm, transformer oil level abnormalities, rupture of the explosion-proof membrane and other phenomena, which in turn causes an imbalance in the internal pressure of the equipment, and in serious cases, damage to the transformer; clogging conditions need to be immediately shut down to check, clean up the clogged material or direct replacement of the breather.
The core reason for oil cup spraying and overflowing is that the internal pressure of the transformer is too high or the flow resistance of the breather is too large; when dealing with it, it is necessary to prioritize checking the breather to see if it is clogged, and then clean it up or replace it in time, and at the same time, investigate the root cause of the abnormal internal pressure of the transformer.
Maintenance-free intelligent respirator has built-in temperature, humidity and pressure sensors, which can monitor the operation parameters in real time; the desiccant can be automatically heated and regenerated when saturated, without manual replacement; it supports remote data transmission, realizing the “zero contact” monitoring of the equipment status; it is equipped with a visualization interface, which can intuitively display the working status; it can significantly prolong the maintenance cycle and reduce equipment It can significantly extend the maintenance cycle and reduce the cost of equipment operation and maintenance.
Daily inspection needs to focus on observing two core indicators: the color status of the color-changing silica gel (to determine the degree of moisture absorption saturation), the oil level in the oil cup (to ensure that meets the standard requirements); found abnormalities need to be dealt with in a timely manner, to ensure that the transformer insulating oil is dry and clean, and to maintain the equipment for long-term reliable operation.
