• Input : 4-32VDC/4-16mA
• Input Green LED Indication
• Output : 24-480(47-63 Hz), 25Amp
• PIV : 800, I²T : 450A²S for 9.6mS
• Zero Cross Over SSR design
• Body insulation : 6kV for 1min
• I/P. to O/P. insulation : 6kV for 1min
• Long life cycle Up to 10¹¹ cycles
• Inbuilt surge voltage protection of 2700Vrms

101 ZDA 48 25 01 Unison SSR DC to AC 25 Amp Solid State Relay

Product Description

The Unison 101 ZDA 48 25 01 is a high-performance 25 Amp DC to AC Solid State Relay (SSR) designed for reliable and maintenance-free switching of AC loads using a DC control signal. Featuring zero cross switching technology, this SSR minimizes electrical noise, reduces inrush current, and extends the service life of both the relay and connected equipment. It is an excellent replacement for conventional electromechanical relays in industrial automation applications where fast, silent, and reliable switching is required.

With a 4–32 VDC control input and 24–480 VAC output, the relay is compatible with PLCs, PID temperature controllers, microcontrollers, and industrial control systems. Since there are no moving contacts, the relay provides vibration-resistant operation, fast switching, and a significantly longer operating life than mechanical relays.

The 101 ZDA 48 25 01 is suitable for switching resistive and inductive loads in heating systems, packaging machines, plastic processing equipment, textile machinery, industrial ovens, and process automation systems. It incorporates opto-isolation between input and output circuits for improved electrical safety and system protection. The relay also features LED input indication for quick status monitoring during installation and maintenance.

For reliable operation at rated current, a correctly sized heat sink should always be used. The compact panel-mount design allows easy installation inside electrical control panels while delivering dependable long-term performance in demanding industrial environments.

Key Features

• Model: 101 ZDA 48 25 01
• Brand: Unison
• DC to AC Solid State Relay
• 25 Amp load current
• Zero Cross Switching
• Input: 4–32 VDC
• Output: 24–480 VAC, 47–63 Hz
• Fast, silent switching
• Optically isolated input and output
• Long operational life with no moving contacts
• LED input status indication
• Compact panel-mount design
• Suitable for PLC and PID controller outputs

Technical Specifications

Use an appropriately rated heat sink for continuous full-load operation.

Applications

The Unison 101 ZDA 48 25 01 SSR is commonly used for:

• Temperature control using PID controllers
• Resistance heater switching
• Motor starting
• UV lamp control
• Plastic welding machines
• Industrial ovens and furnaces
• Packaging and sealing machines
• Textile machinery
• Food processing equipment
• Industrial automation control panels

Why Buy from Voltkart?

• Genuine Unison products
• GST Invoice provided
• Pan India delivery
• Bulk pricing available for OEMs and panel builders
• Technical assistance for product selection
• Trusted supplier of industrial automation products

Frequently Asked Questions

1. What is the control input voltage of the Unison 101 ZDA 48 25 01?

The relay operates with a 4–32 VDC control input, making it compatible with most PLCs, PID controllers, and automation systems.

2. Does this SSR require a heat sink?

Yes. For continuous operation near its rated 25 Amp load, an appropriately sized heat sink is recommended to ensure reliable performance and longer service life.

3. What is the advantage of Zero Cross switching?

Zero Cross switching turns the relay on when the AC waveform crosses zero voltage, reducing electrical noise, minimizing surge current, and increasing the life of the connected load.

Related Products & Collections

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