In process control, security, communication nodes, and industrial equipment that require power-off maintenance, ordinary switch mode power supplies can only solve the problem of "supplying power when there is mains power", but cannot solve the problem of "how long the system can last after the mains power disappears". TRACO POWER's TIS600-124UDS is a DC uninterruptible power supply system designed for this type of demand: it integrates a 600 W level 24 VDC switching power supply, external battery charging management, uninterrupted switching, and alarm relay into a DIN rail mounted metal housing. For on-site engineers, what really needs to be clarified is often not whether it is a 24 V power supply, but how to match the battery pack, how to set the charging current, what conditions trigger the power-off switch, how to connect the alarm contacts to the PLC, and where to start when "battery does not charge", "power-off does not switch", or "low battery false alarm" occurs.
Model positioning and electrical boundaries
TIS600-124UDS belongs to the DC-UPS version of the TIS series, with optional input of 115/230 VAC, nominal output of 24 VDC, maximum output power of 600 W, and maximum output current of 24 A. The difference between it and the ordinary TIS600-124 is the addition of a battery charger, battery switch logic, mains fault detection, and battery low voltage detection internally. The RED version is not the same type of product as the TIS xxx RED redundant version and TIS xxx SIG power fault signal version: the RED version is used for up to 5 parallel N+1 redundant systems, with decoupling diodes, current sharing lines, and unit fault alarms; SIG version provides AC Powerfall, DC OK, and Remote ON/OFF; The core of UDS version is battery management and uninterrupted backup. When selecting, the additional functions of UDS, RED, and SIG cannot be considered together, and the product documentation clearly states that redundant options cannot be combined with other options.
From the perspective of General Electric specifications, the TIS series has an input voltage range of 93-132 VAC and 187-264 VAC, with an input frequency of 47-63 Hz. The typical efficiency value of TIS600 is 88%, with a switching frequency of about 80 kHz, output ripple and noise less than 50 mV peak to peak, short-circuit protection of about 110% constant current limit and automatic restart, and overvoltage protection trigger point of about 140% of the nominal output. The working environment is between -25 ° C and 70 ° C, with a maximum relative humidity of 95% non condensing. If the temperature is above 50 ° C, the rating will be reduced by 2%/° C. That is to say, the TIS600-124UDS can be designed at 600 W at 50 ° C, but the available power will significantly decrease at 70 ° C. If the on-site cabinet has poor heat dissipation and battery charging and load coexist, it is easier to reach the power boundary. The shell is made of aluminum chassis with stainless steel cover, with a protection level of IP20, suitable for installation inside the control cabinet. It is clamped with a 35 mm DIN rail, and the TIS600 uses screw terminal blocks. When wiring, it should be constructed according to the terminal identification and torque requirements.
The working logic and battery management of DC-UPS
The normal working logic of TIS600-124UDS can be understood as "mains power priority, battery backup, automatic switching". When there is mains power, the power supply outputs 24 VDC to the load on one hand, and charges the external battery through an internal charger on the other hand; When the mains power disappears or falls below the detection threshold, the battery automatically connects to the DC output through internal switch logic, and the switching process does not interrupt the load power supply; After the mains power is restored, the battery is disconnected, the load is powered by the mains power again, and the charger resumes charging. The backup time is not limited by the power source itself, but depends on the battery capacity and load current. The battery pack provided in the product information is TIS 24-70 AP, 24 VDC/7.0 Ah, maximum allowable charging current of 2.4 A, charging voltage range of 27-27.6 VDC, temperature coefficient of about -36 mV/° C, charging working temperature of -15~50 ° C, load working temperature of -20~60 ° C, average standby life of about 4~5 years at 20 ° C, cable length of 1 m, wire diameter of 4.0 mm ², weight of about 5.9 kg. If TIS3000-124UDS is selected, it corresponds to a 3.2 Ah battery pack and a 1.2 A charging current.
The charging current of TIS600-124UDS is set at 2.4 A in the factory, with an adjustable range of 0.25-2.5 A. This parameter is crucial: the charging current is not necessarily the larger the better, it must be less than the maximum charging current allowed by the battery pack, taking into account battery temperature and service life. The data also shows that maintaining a charging current of less than 50 mA at 27.3 VDC indicates that the battery will enter a float charging state after being fully charged and will not continue to experience high current impact. When charging the battery, the output current will decrease by about 1.4 times the charging current. For example, when the charging current is set to 2.4 A, the available output current needs to be deducted by about 3.36 A. If the on-site load is close to 24 A and the battery is also in the charging stage, the total power and heat dissipation must be recalculated, otherwise there may be a drop in output voltage or intermittent overload.