Siemens ep1333-4ba00

By Abdullah Zahid
13 min read
Siemens 6EP1333-4BA00 SIMATIC PM 1507 24V 8A DIN-rail power supply for S7-1500 control cabinet

Siemens 6EP1333-4BA00 SIMATIC PM 1507 24 V/8 A Power Supply: Complete Specs, Selection Guide, and S7-1500 Alternatives

Controls engineers specifying a power supply for a new or retrofit SIMATIC S7-1500 system typically arrive at the Siemens 6EP1333-4BA00 after one of two routes: it was called out in a system design, or they are validating whether the 8 A output rating actually covers their total 24 V DC load. Either way, the decision comes down to three hard numbers — 24 V DC output, 8 A continuous current, and 75 mm DIN-rail width — and whether the galvanic isolation, soft-start behavior, and safety certifications align with the installation environment. This article covers the verified electrical specifications, mounting requirements, protection features, and honest comparison with higher-current and alternative variants so you can confirm or correct your selection before placing the order.

If you have already confirmed this is the correct part for your system, check current pricing and availability at LeadTime.ca — ships worldwide.

Who Should Buy the Siemens 6EP1333-4BA00 — and Who Shouldn't

The Siemens 6EP1333-4BA00 is the right choice for engineers powering a SIMATIC S7-1500 CPU with a combined 24 V DC field load that fits within an 8 A continuous rating. It is a direct-fit, certified module that avoids the integration guesswork associated with third-party supplies.

  • Your AC mains supply is single-phase 120 V or 230 V at 50 or 60 Hz
  • Your total 24 V DC load — CPU, I/O modules, sensors, solenoids — sums to 8 A or less with a reasonable safety margin
  • Your DIN-rail cabinet has 75 mm of horizontal space and at least 40 mm of vertical clearance above and below the mounting position
  • The installation environment is non-hazardous (no ATEX, IECEx, or UL hazloc requirement) and ambient temperature stays within 0–60 °C for horizontal mounting or 0–40 °C for vertical mounting
  • You require galvanic isolation and safety extra-low voltage compliance per EN 60950-1, EN 50178, and EN 61131-2

If your 24 V DC load exceeds 8 A continuous, you need the 16 A or 20 A SIMATIC PM variant. If your installation is in a classified hazardous area, the correct SKU is 6EP1333-4BA00-8AA0. If you need parallel redundancy or hot-standby operation, this model does not support it — consult Siemens for a dual-supply configuration.

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What the Siemens 6EP1333-4BA00 Actually Does in a Control System

The Siemens 6EP1333-4BA00 — officially designated the SIMATIC PM 1507 24 V/8 A stabilized power supply — is a single-phase AC-to-DC converter engineered specifically for the SIMATIC S7-1500 automation platform. Its core job is straightforward: take 120 V or 230 V AC from facility mains and deliver a stable, galvanically isolated 24 V DC rail at up to 8 A to the S7-1500 CPU, connected I/O modules, and field devices such as sensors, solenoids, and motor contactors.

What distinguishes the PM 1507 from a generic DIN-rail power supply is the combination of soft-start behavior, a secondary overvoltage control loop that clamps output below 28.8 V, and electronic short-circuit protection with automatic restart. These features are not just convenience — they protect S7-1500 CPU memory during brown-outs, prevent inrush transients from triggering spurious CPU resets, and eliminate the need for external current-limiting fuses at the output rail in many standard configurations. The module provides a minimum 20 ms buffering time during mains failure at 93–187 V input, which gives the S7-1500 CPU enough time to detect the power loss and execute an orderly shutdown before voltage collapses.

The module delivers a typical active power output of 192 W with a typical power loss of 19.6 W, occupies 75 mm of DIN-rail width, and carries an MTBF rating of 1,362,918 hours at 40 °C — a figure that reflects the design reliability expected from a component at the heart of a production control system. IP20 protection keeps it suitable for standard control cabinet environments but not open or wet locations.

Typical S7-1500 Power Architecture Using the PM 1507

The 6EP1333-4BA00 sits directly between the AC distribution panel and the S7-1500 CPU, acting as the single power conditioning point for the entire PLC segment. Understanding this position in the chain helps identify what connects upstream and downstream before specifying the module.

  • Facility AC distribution panel → single-phase 120 V or 230 V AC branch circuit with upstream circuit protection
  • AC branch circuit → screw-clamp L/N/PE input terminals on the 6EP1333-4BA00
  • 6EP1333-4BA00 output rail → SIMATIC S7-1500 CPU power input (L+ and M, 24 V DC)
  • Same 24 V DC rail → SIMATIC ET 200 I/O modules, digital and analog input modules, signal boards
  • 24 V DC rail → field devices: proximity sensors, solenoid valves, motor contactors, pilot lights

Where Engineers Deploy the 6EP1333-4BA00

In discrete manufacturing — automotive, electronics assembly, consumer goods — the 6EP1333-4BA00 is the standard power supply specification for single-zone S7-1500 control cabinets managing one production line segment. A typical cabinet in this application runs a CPU with four to eight I/O modules plus solenoid drivers, landing comfortably within the 8 A rating.

Pharmaceutical and food processing facilities favour this module because the galvanic isolation and EN 50178 / EN 60950-1 compliance satisfy machine safety and hygienic area requirements without requiring a separate isolation transformer at each panel. Packaging machinery OEMs building S7-1500-based systems use the PM 1507 as a standard BOM item because the 75 mm width fits their standardized cabinet layouts.

Retrofit and upgrade projects — particularly replacing legacy SIMATIC PM 1506 or PM 1505 units — represent a significant share of PM 1507 orders. Engineers upgrading older S7-300 or S7-400 systems to S7-1500 need a power supply certified for the new platform, and the 6EP1333-4BA00 is the direct SIMATIC-family replacement. For distributed automation edge nodes where cabinet space and thermal budget are constrained, the compact 75 mm form factor and 0–60 °C operating range (horizontal) make this the preferred selection over larger units.

Application Typical Deployment
Small to mid-size S7-1500 control cabinet Single CPU, 4–8 I/O modules, solenoid drivers; 2–6 A typical load
Production line segment controller Coordinating conveyors, VFDs, and sensor networks for one process zone
Critical PLC with UPS backup PM 1507 paired with external battery module or UPS for ride-through during outages
Retrofit from legacy SIMATIC PM Direct replacement for PM 1506 or PM 1505 in S7-1500 upgrade projects
Distributed automation edge node Remote PLC in multi-point facility where space and thermal budget are constrained

Purchase-Decision Specifications at a Glance

Parameter Value
Input voltage 120 V or 230 V AC, single-phase, 50/60 Hz
Output voltage 24 V DC nominal
Output current 0–8 A rated continuous
Typical active power output 192 W
Typical power loss 19.6 W
Dimensions (W × H × D) 75 mm × 147 mm × 129 mm
Operating ambient temperature 0–60 °C horizontal; 0–40 °C vertical
Degree of protection IP20 (EN 60529)
MTBF at 40 °C 1,362,918 hours
Safety certifications EN 60950-1, EN 50178, EN 61131-2; CB certificate; ATEX: No

Full technical specifications are available on the product page at LeadTime.ca.

PM 1507 vs. PM 1506 vs. PM 1505: Which SIMATIC Power Supply Do You Actually Need?

Model Output Current Compatible Platform Key Differentiator Choose When
6EP1333-4BA00 (PM 1507) 8 A SIMATIC S7-1500 Soft-start, integrated diagnostics, compact 75 mm width Load is 5–8 A; new S7-1500 build or upgrade
SIMATIC PM 1505 5 A SIMATIC S7-1500 Smaller form factor, lower power Minimal load — sensors and logic only, no solenoids or contactors
SIMATIC PM 1506 10 A S7-300 / S7-400 (legacy) Older generation; less integrated diagnostics Existing S7-300/400 systems — not recommended for S7-1500
SIMATIC PM 16 A variant 16 A SIMATIC S7-1500 Higher current; larger DIN-rail footprint (typically 100 mm+) Load exceeds 8 A; multiple CPUs or large I/O base
SIMATIC PM 20 A variant 20 A SIMATIC S7-1500 Highest current in the family Large systems with heavy field load or future expansion headroom required
6EP1333-4BA00-8AA0 (EX variant) 8 A SIMATIC S7-1500 ATEX / IECEx certification for hazardous areas Installation in classified hazardous or intrinsically safe area

If your system load falls between 5 A and 8 A and your platform is SIMATIC S7-1500, the 6EP1333-4BA00 is the correct selection — check current availability at LeadTime.ca.

Expert Verdict: Honest Assessment and Procurement Reality

The Siemens 6EP1333-4BA00 is a well-matched power supply for what it was designed to do: provide a stable, isolated 24 V DC source for a single S7-1500 system segment with a load up to 8 A. The soft-start feature, secondary overvoltage loop clamped at 28.8 V, and electronic short-circuit protection with automatic restart are genuinely useful in industrial environments where mains quality is inconsistent and field wiring faults are a routine maintenance event. The MTBF of 1,362,918 hours at 40 °C is not a warranty figure, but it reflects the design standard expected of a component that controls engineers rarely want to think about once it is commissioned. The 75 mm DIN-rail width and removable input and output terminal blocks make swap-out straightforward — a trained technician can replace the unit in under 30 minutes.

The honest limits are equally clear. Eight amps is the ceiling, and there is no parallel operation support for redundancy. If your load calculation comes in above 7 A after accounting for all sensors, solenoids, and I/O modules, specify the 16 A variant from the outset rather than operating the PM 1507 near its rated limit continuously. The 20 ms minimum buffering time at 93–187 V input is sufficient for the S7-1500 to detect a power loss and execute a safe shutdown, but it is not a substitute for a true UPS if your application requires extended ride-through. And if your installation environment requires ATEX or IECEx certification, the standard 6EP1333-4BA00 is the wrong part — the EX-rated variant 6EP1333-4BA00-8AA0 is the correct SKU.

From a procurement standpoint, this is not a commodity item with same-day stock everywhere. Typical lead times run two to four weeks for distributor stock and six to eight weeks for special orders. For mission-critical systems, maintaining at least one spare unit per five to ten deployed modules is a practical strategy. Volume orders of ten or more units frequently qualify for negotiated pricing. If this matches your system requirements, view current stock and pricing at LeadTime.ca.

For volume pricing or to confirm lead time before committing to a build schedule, contact the LeadTime.ca team directly — we ship worldwide.

Wiring and Installation Overview

  • AC input wiring connects to screw-clamp terminals labeled L, N, and PE — use 0.5–2.5 mm² copper or tinned wire; always connect the protective earth (PE) to the designated terminal before energizing
  • DC output connects via spring-loaded terminals labeled L+ (positive) and M (common/return) at 0.5–2.5 mm², using the press-to-insert release mechanism; verify polarity with a multimeter before applying power to the CPU
  • Mount on standard 35 mm DIN rail in the horizontal orientation for maximum thermal rating (0–60 °C); vertical mounting restricts the operating range to 0–40 °C — maintain 40 mm clearance above and below the module in both orientations
  • On initial power-up, the yellow LED indicates the soft-start delay is in progress; steady green LED confirms 24 V DC output is within nominal range; a red LED indicates a fault condition requiring inspection of output wiring and load current
  • No external circuit breaker is integrated in the module — upstream AC branch protection must be provided as part of the system electrical design; refer to official Siemens installation documentation for full wiring procedures and conductor sizing tables

How Soft-Start, Short-Circuit Protection, and Buffering Work

The soft-start function limits inrush current and prevents output voltage overshoot when AC power is first applied. The output voltage rises to 24 V DC within a maximum response delay of 1.5 seconds, with a typical voltage increase time of 10 ms once the ramp begins. This eliminates the sharp voltage transients that can trigger false CPU resets or corrupt initialization routines in sensitive S7-1500 configurations.

Automatic voltage regulation maintains 24 V DC within a control precision of approximately 2% under resistive load changes (50/100/50% load step), with a setting time of approximately 5 ms for a 10–90% load transition. Residual ripple is held to a maximum of 50 mV, with voltage peaks capped at 150 mV — important for analog I/O accuracy and sensor stability on the same rail.

Short-circuit protection is electronic, not fuse-based. When the output current exceeds the current limiting range of 8.4–9.6 A (typical 9 A), the module electronically shuts down power delivery and automatically restarts once the fault is cleared. The secondary overvoltage control loop monitors output voltage continuously and enters current-limiting mode if the output approaches 28.8 V, protecting all downstream devices from mains transient coupling. During a mains failure event, the module provides a minimum buffering time of 20 ms at input voltages of 93–187 V, giving the S7-1500 sufficient time to detect the loss and initiate an orderly shutdown without data corruption.

Wrong-Part Prevention: Eight Checks Before You Order

Before submitting a purchase order for the Siemens 6EP1333-4BA00, work through each of the following checks. Skipping these is the most common cause of returns, commissioning delays, and field failures with this part number.

  1. Verify input mains voltage at site: Does your AC supply provide 120 V or 230 V single-phase? (This model does not auto-sense all voltages; it requires either 120 VAC OR 230 VAC, not 3-phase, not 48/60 V DC)
  2. Confirm S7-1500 CPU model and version: Is your PLC a genuine SIMATIC S7-1500 (not S7-1200, S7-300, or other series)?
  3. Check total current demand: Add up all 24 V DC loads (CPU, I/O modules, sensors, solenoids). Does the total exceed 8 A continuous? If yes, you need a larger module (16 A or 20 A variant).
  4. Confirm DIN-rail mounting space: Is your cabinet's DIN rail accessible for a 75 mm wide module with 40 mm top and bottom clearance?
  5. Verify safety/compliance requirement: Is this deployment in a hazardous or intrinsically safe area? If yes, do not use standard 6EP1333-4BA00; you must order the EX-rated variant (6EP1333-4BA00-8AA0).
  6. Check power quality and mains surges: If your site has frequent power anomalies or high inrush currents (welders, large motor starters), confirm your facility electrical design supports this module's surge immunity (2.3x overvoltage, 1.3 ms rating).
  7. Validate cabinet thermal environment: Is the ambient temperature during operation within 0–60 °C (horizontal) or 0–40 °C (vertical mount)? Overheating will cause the module to derate or shut down.
  8. Confirm spare parts strategy: Are replacement modules in your spares inventory or easily available through your distributor? Long lead times can interrupt production.

If any check raises a flag, contact the LeadTime.ca team before ordering — we can help confirm the correct SKU or identify the appropriate alternative variant.

Frequently Asked Questions

Is the 6EP1333-4BA00 compatible with both 120 V and 230 V AC input on the same unit?

The Siemens 6EP1333-4BA00 accepts either 120 V or 230 V AC single-phase at 50 or 60 Hz, but it is not a universal auto-ranging supply that handles all voltages simultaneously. Confirm your facility mains voltage matches one of these two ratings before ordering. Three-phase input, 48 V DC, or 60 V DC sources are not compatible with this module.

How do I know if 8 A is enough for my S7-1500 system?

Sum the 24 V DC current draw of every device on the rail: the S7-1500 CPU, each I/O module, all digital output loads (solenoids, contactors, pilot lights), and any powered sensors. If that total exceeds 8 A, or if it approaches 8 A and future expansion is likely, specify the 16 A or 20 A SIMATIC PM variant instead. A practical design margin is to target no more than 6 A of continuous load on the 8 A rated module.

What does the 20 ms buffering time actually protect against?

The minimum 20 ms buffering time at 93–187 V mains input allows the SIMATIC S7-1500 CPU to detect the loss of AC power and begin an orderly shutdown sequence before the 24 V DC rail collapses. This prevents in-process data corruption and protects program state in CPU memory during brief brown-outs or momentary supply interruptions. It is not intended as extended ride-through protection — for longer outages, a separate UPS or battery backup module is required.

Can I use the 6EP1333-4BA00 in a hazardous or classified area?

No. The standard 6EP1333-4BA00 carries no ATEX, IECEx, or UL hazardous location approvals. For installations in classified hazardous areas, the correct part number is 6EP1333-4BA00-8AA0, which is a different SKU with the appropriate EX-rated certification. Do not substitute the standard module in these environments.

What does the red LED indicate and how do I clear it?

The red LED illuminates when the module detects a short-circuit at the output, an overcurrent condition beyond the 8.4–9.6 A current limiting range, an internal overvoltage event, or a thermal shutdown. To clear it: switch off AC mains power, disconnect all output loads, wait approximately 30 seconds, then restore mains. If the red LED persists with no load connected, the module itself may require replacement. The electronic protection circuit is designed to restart automatically once a wiring fault is resolved.

Does the 6EP1333-4BA00 support parallel operation for redundancy?

No. This model does not support parallel operation. If your application requires power supply redundancy or hot-standby capability, this module is not the correct choice. Consult Siemens application engineering or your system integrator for a dual-supply configuration or evaluate dedicated redundancy modules designed for parallel current sharing.

Why Order From LeadTime.ca

  • Global shipping on industrial automation components including the Siemens 6EP1333-4BA00 — no geographic restrictions on orders
  • Sourcing support for hard-to-find or long-lead SKUs, including EX-rated variants and legacy SIMATIC power supply modules
  • Volume pricing available for OEM panel builders and procurement teams ordering ten or more units
  • Direct response from a team that understands SIMATIC system architecture — not a generic parts catalog

At-a-Glance Summary

  • Official product name: SIMATIC PM 1507 24 V/8 A stabilized power supply for SIMATIC S7-1500
  • Catalog number: 6EP1333-4BA00
  • Input: 120 V or 230 V AC, single-phase, 50/60 Hz
  • Output: 24 V DC nominal, 0–8 A continuous rated current
  • Typical active power output: 192 W; typical power loss: 19.6 W
  • Overvoltage protection: secondary control loop clamps output below 28.8 V
  • Short-circuit protection: electronic shutdown with automatic restart; current limit range 8.4–9.6 A
  • Buffering time on mains failure: minimum 20 ms at 93–187 V input
  • Dimensions: 75 mm W × 147 mm H × 129 mm D; weight approximately 736 g
  • Operating temperature: 0–60 °C horizontal; 0–40 °C vertical; storage –40 to +85 °C
  • Protection: IP20 per EN 60529; galvanic isolation primary to secondary
  • Certifications: EN 60950-1, EN 50178, EN 61131-2, EN 55022 Class B, EN 61000-3-2; CB certificate; ATEX: No
  • MTBF at 40 °C: 1,362,918 hours
  • Hazardous area alternative: 6EP1333-4BA00-8AA0 (EX-rated variant, separate SKU)
  • Does not support parallel redundancy operation