901 ZDA 48 40 01 AL5, Unison SSR Dc to Ac, 40amp

Specifications (existing/cleaned up)

• Model: Unison 901 ZDA 48 40 01 AL5
• Type: Solid State Relay (SSR), DC control input / AC load output
• Load Current: 40A
• Control Input: DC (typically 4-32V DC control signal)
• Load Voltage: AC output, typically 90-480V AC range (model-dependent)
• Switching Type: Zero-cross or random-fire (model/suffix dependent)
• Mounting: Panel/heatsink mounting with mounting holes
• Isolation: Optically isolated input-to-output

What is this product?

The Unison 901 ZDA 48 40 01 AL5 is a solid state relay that uses a low-voltage DC control signal to switch a high-current AC load, with no moving mechanical parts involved. It's used wherever fast, silent, wear-free switching of AC loads such as heaters is needed.

Where is it used?

• Industrial heater control panels (band heaters, cartridge heaters, oven elements)
• Plastic extrusion and injection molding machine temperature zones
• Packaging machinery with heat-sealing elements
• Furnace and drying chamber temperature control loops
• Process control panels requiring frequent ON/OFF cycling of AC loads

Key technical advantages

The 901 ZDA 48 40 01 AL5 stands out because, unlike mechanical contactors, it has no moving parts to wear out, making it ideal for applications with frequent switching cycles like PID-controlled heater loops where a mechanical contactor would fail quickly from contact arcing and mechanical fatigue. Its optically isolated design protects sensitive control electronics (PLCs, temperature controllers) from electrical noise and voltage transients on the load side. The 40A rating suits small-to-mid size heater loads efficiently without oversizing, and Unison's build quality is designed to handle the electrical noise and thermal cycling common in Indian industrial heating setups. The silent, spark-free switching action also reduces electrical interference with nearby sensitive instrumentation, a benefit over mechanical relay switching.

Why buy from Voltkart?

Voltkart is an authorized dealer for Unison, so the 901 ZDA 48 40 01 AL5 you receive is 100% genuine with full manufacturer warranty — not a counterfeit or grey-market unit. Every order comes with a proper GST invoice, PAN India delivery with fast dispatch from our Delhi (Bhagirath Palace) warehouse, and direct WhatsApp support (+91 98996 68881 / 8800754881) for help with heatsink sizing, control wiring, or bulk order pricing.

FAQs

Q: Does the 901 ZDA 48 40 01 AL5 need a heatsink for continuous 40A operation?
A: Yes, SSRs dissipate heat proportional to load current even in normal operation, so a properly sized heatsink is essential for continuous 40A duty — undersized cooling is the most common cause of premature SSR failure, so let us know your enclosure size and ambient conditions and we can help size the right heatsink.

Q: What DC control voltage does this SSR accept?
A: This model accepts a DC control signal, typically in the 4-32V DC range common for PLC and temperature controller outputs — please confirm your controller's output signal type when ordering so we can verify compatibility.

Q: How is the 901 ZDA 48 40 01 AL5 different from the 901 ZDA 60 50 01 AL5?
A: The 48 40 variant is rated for 40A load current while the 60 50 variant handles 50A — beyond the current rating, frame/heatsink size also differs to match thermal dissipation needs, so choose based on your actual heater load current with some safety margin.

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