Key Technical Specifications
| Parameter | Value |
|---|---|
| Input Voltage | 12–24 VDC Nominal (10–30 VDC Range) |
| Redundant Current | 2 x 20 A (-40°C to +60°C) |
| Parallel Current | 1 x 40 A (-40°C to +60°C) |
| Voltage Drop | 0.5 V (Input to Output) |
| Efficiency | > 97% |
| Power Dissipation | 10 W Max (at 20 A output) |
| Connection Type | Screw Terminals (M4, 0.5–16 mm²) |
| Mounting | 35 mm DIN Rail (EN 60715) |
| Dimensions (WxHxD) | 50 x 130 x 125 mm |
| Protection | Reverse Polarity, Transient Overvoltage |
Product Introduction
The Phoenix QUINT-DIODE/12-24DC/2×20/1×40 2320157 is a DIN-rail mounted redundancy module designed to decouple two parallel 24VDC power supplies. It uses internal diodes to prevent a fault in one supply from dragging down the entire bus, ensuring continuous power to critical PLCs and safety controllers.This module handles up to 40A in parallel mode or 2x20A in redundant mode, with a mere 0.5V voltage drop across the diodes. Field technicians appreciate the >97% efficiency, which keeps cabinet temperatures manageable even at full load. The screw terminals accept up to 16mm² wire, but I’ve seen installers struggle with 10mm² ferrules in tight spaces—always pre-strip and crimp before attempting insertion. The module also provides selective fusing support (120A for 15ms), allowing downstream breakers to trip before the diode module itself is damaged.
Installation & Configuration Guide
Preparation (10 min)
- Verify both power supplies are set to the same output voltage (within 0.5V of each other).
- Confirm the DIN rail is grounded; the module chassis requires protective earth.
- Gather insulated screwdrivers and a torque driver (1.2–1.5 Nm for M4 screws).
- Safety: Lock out both power supplies before wiring. Reverse polarity will destroy the internal diodes instantly.
Removal (5–10 min)
- Disconnect all field wiring from input and output terminals.
- Release the DIN rail latch using a flathead screwdriver.
- Slide the module upward and off the rail.
- Inspect the terminal blocks for heat discoloration; darkened plastic indicates prior overcurrent events.
Installation (10 min)
- Snap the module onto the 35mm DIN rail; ensure the latch clicks securely.
- Connect Power Supply 1 to Input 1 (+/-), Power Supply 2 to Input 2 (+/-).
- Connect the load to the Output (+/-) terminals.
- Torque all M4 screws to 1.2–1.5 Nm; loose terminals at 40A will cause arcing and fire.
Power-On & Test (10 min)
- Energize Power Supply 1 only; measure output voltage at the module terminals.
- Energize Power Supply 2; verify both supplies share the load (current should be roughly equal).
- Disconnect Power Supply 1; verify the output voltage remains stable and the load continues to operate.
- Reconnect Power Supply 1; verify no inrush current spike trips the supply’s protection.
Troubleshooting Quick Reference
| Symptom | Probable Cause | Immediate Check |
|---|---|---|
| Output Voltage Low | High Load / Bad Supply | Measure each supply directly; check for 0.5V drop across module. |
| One Supply Overloaded | Voltage Mismatch | Adjust supply voltage; difference must be <0.5V. |
| Module Overheating | Loose Terminal / Overload | Retighten screws to 1.5 Nm; measure load current. |
| No Output | Blown Input Fuse / Wiring | Verify 24VDC at both input terminals; check polarity. |
| Intermittent Faults | Vibration / Loose DIN Clip | Check DIN rail end-caps; add adhesive pad if needed. |
| Diode Failure | Reverse Polarity Event | Replace module. Internal diodes are not field-repairable. |
Dimensions, Mounting & Wiring Notes
- Form Factor: 50mm Width, 130mm Height, 125mm Depth.
- Mounting: Standard 35mm DIN Rail; no minimum spacing required between modules.
- Wiring Note: Use copper conductors only. Aluminum wire oxidizes in screw terminals and causes hot spots at high current.
- Heat Dissipation: At 40A, the module dissipates ~20W. Ensure cabinet ventilation or mount near a cooling fan. Do not install directly above heat-sensitive components.
FAQ
Can I use this module with 48VDC supplies?
No. The QUINT-DIODE/12-24DC/2×20/1×40 2320157 is rated for 12-24VDC nominal (30VDC max). Applying 48VDC will exceed the reverse voltage rating of the internal diodes and cause catastrophic failure. Use the QUINT-DIODE/40-60DC version for 48V systems.My two supplies are fighting each other. One gets hot.
The supplies are not voltage-matched. Adjust the trim pot on the cooler supply until both output currents are within 10% of each other. I’ve seen 1V difference cause one supply to carry 90% of the load while the other sits idle.Is this the same as the newer 2907719?
Functionally, yes. The 2907719 (QUINT4-DIODE) is the successor with updated diagnostics and a slightly different housing. The electrical specs (2x20A/1x40A) are identical. If you’re replacing a 2320157, the 2907719 is a direct drop-in replacement, but verify the 50mm width matches your existing layout.Can I parallel three supplies using two of these modules?
No. This module is designed for exactly two inputs. Paralleling three supplies requires a different topology (e.g., two modules cascaded, which is not recommended due to cumulative voltage drop). Use a dedicated 3-channel redundancy controller instead.Do you test the diode forward voltage drop before shipping?
Yes. We measure the voltage drop across each diode at 20A and 40A. Any unit exceeding 0.6V drop at rated current is rejected. The test report is included in the box. High forward voltage indicates a degraded or counterfeit diode.My module is hot to the touch at 30A. Is this normal?
Yes, within limits. At 30A, expect ~15W dissipation, which translates to a surface temperature of 50-60°C. If it’s too hot to touch (>70°C), check the terminal torque and load current. Also verify ambient temperature; derating begins above 60°C.Is hot-swapping supported?
Yes, but with caution. Disconnect one supply at a time, allowing the remaining supply to pick up the full load. Do not disconnect both simultaneously unless the load has local energy storage (capacitors/batteries). The diodes prevent backfeed, but sudden load changes can cause voltage sags.
