Midnite Solar MNE-240 E-panel Owner's Manual

The Midnite Solar MNE-240 E-panel is a pre-wired AC/DC electrical enclosure designed for use with Midnite Solar and other compatible charge controllers and inverters in off-grid and grid-tied solar systems. It integrates critical safety components, including DC and AC disconnects, overcurrent protection, and surge protection, into a single, National Electrical Code (NEC) compliant enclosure. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

Features at a Glance

Key components: NEMA 3R rated enclosure, DC Disconnect breaker, AC Output breaker, PV and Battery busbars, Grounding busbar, Surge Protection Device (SPD), and pre-drilled knockouts for conduit.

Installation

Unpack and inspect contents. Mount on a sturdy, vertical surface.

1. Mounting: Select location protected from direct weather exposure if possible. Use provided hardware to secure enclosure.
2. Grounding: Connect equipment grounding conductor (EGC) from system ground rod to the grounding busbar first.
3. DC Wiring: Route PV array cables through conduit. Connect PV+ to PV busbar via DC disconnect. Connect PV- to battery negative busbar.
4. AC Wiring: Route inverter/generator output cables. Connect to the AC output breaker terminals.
5. Controller/Inverter Mounting: Install charge controller and inverter inside the enclosure using internal mounting points.

WARNING! Installation must be performed by a qualified electrician in accordance with NEC and all local codes. Disconnect all power sources before working inside the panel.

First-Time Setup

After mechanical installation, proceed with electrical commissioning.

1. Pre-Power Check: Verify all wire terminations are tight. Ensure DC polarity is correct. Confirm all breakers are in the OFF position.
2. DC Power-Up: Turn ON the DC Disconnect breaker to apply PV power to the charge controller.
3. Controller Configuration: Program the charge controller (e.g., Midnite Classic) for your specific battery type (Flooded, AGM, Lithium, etc.).
4. AC Power-Up: Turn ON the AC Output breaker to connect the inverter to the load panel or generator.
5. System Verification: Monitor controller display for proper charging. Check for correct voltage at AC outlets.

CAUTION! Always turn DC and AC breakers OFF before making any wiring changes. Use appropriate personal protective equipment (PPE).

Specifications

• Model: MNE-240 E-panel
• Enclosure: Steel, NEMA 3R (Rainproof)
• Max DC Voltage: 150VDC (Standard), higher voltage models available.
• DC Breaker: 63A (or as specified by system design)
• AC Breaker: 30A, 240VAC (or as specified)
• Busbar Rating: 200A continuous
• Surge Protection: Varies by model (e.g., 40kA, Type 1/2)
• Dimensions: Approximately 24" H x 18" W x 8" D (verify with specific model)
• Weight: Approximately 35 lbs (empty)
• Compliance: Designed to meet NEC 2017/2020, UL standards where applicable.

Controls and Connections

Primary controls are the DC and AC breaker handles. All connections are made to clearly labeled terminals inside.

External: Breaker handles (DC DISCONNECT, AC OUTPUT), Conduit knockouts, Mounting points.

Internal Terminals:
PV (+): Connects to positive from solar array via DC breaker.
Battery (-): Common negative busbar for battery, PV, and controller.
AC Out: Terminals for Line 1, Line 2, Neutral, Ground from inverter/generator.
Ground Bus: For all equipment grounding conductors.
SPD Terminals: For connecting surge protector leads to DC/AC lines and ground.

Connecting System Components

Follow the system schematic typically provided with the E-panel or your charge controller.

1. PV Array: PV+ to DC breaker input. PV- to Battery (-) busbar.
2. Charge Controller: PV Input terminals to corresponding busbars/breaker output. Battery terminals to battery cables. Load terminals if used.
3. Battery Bank: Battery+ cable to controller's battery+ terminal. Battery- cable to Battery (-) busbar.
4. Inverter: DC Input terminals to battery cables. AC Output terminals to the AC Output breaker inside the E-panel.
5. Grounding: Connect enclosure, all metal parts, and SPD to the central grounding busbar.

Tip: Use copper conductors only. Torque all connections to manufacturer specifications. Apply anti-oxidant compound to aluminum busbars if present.

System Operation & Monitoring

Operation is largely automatic once configured. Monitoring is done via the charge controller display.

1. Normal Operation: With breakers ON, the charge controller will manage battery charging from the PV array. The inverter will convert DC to AC for loads.
2. Disconnecting Power: To shut down system, turn OFF AC Output breaker first (remove load), then turn OFF DC Disconnect breaker (remove source).
3. Monitoring: Check charge controller screen for:
   • Battery Voltage and State of Charge
   • PV Array Voltage and Current
   • Daily/Amp-Hours harvested
   • Error or status messages
4. Load Management: Ensure connected loads do not exceed the continuous rating of the inverter or AC breaker.

WARNING! Do not open the enclosure while energized. Live DC and AC voltages are present and can cause severe injury or death.

Safety Features

DC & AC Disconnects: Provide a means to isolate power sources for maintenance.
Overcurrent Protection: Breakers protect wiring from overloads and short circuits.
Surge Protection: Protects sensitive electronics from voltage spikes caused by lightning or grid events.
Grounding: Proper bonding and grounding provides a path for fault current and reduces shock hazard.
Enclosure: Protects components from weather and prevents accidental contact with live parts.

Care & Maintenance

Periodic inspection is required for safe operation.

1. Visual Inspection (Bi-Annually): Check for signs of corrosion, loose wires, overheating (discoloration), or physical damage.
2. Termination Check (Annually): With power OFF, verify critical connections are tight to specified torque.
3. Cleaning: Keep vents clear of debris. Wipe exterior with a dry cloth. Do not use water or cleaners inside.
4. SPD Status: Check indicator window on Surge Protector. Replace if status shows "FAIL" or after a major surge event.

CAUTION! Always de-energize the system completely (PV covered, batteries disconnected) before performing any internal maintenance.

Regulatory Information

This equipment is intended for installation by qualified personnel in accordance with the National Electrical Code (NEC), ANSI/NFPA 70, and all applicable state and local codes. The installer is responsible for compliance with all regulations. Midnite Solar is a registered trademark. For technical support, system design assistance, and to locate a certified installer, visit www.midnitesolar.com or contact Midnite Solar Inc.

Troubleshooting

Reset: For electronic components (controller/inverter), consult their respective manuals for reset procedures.

Service & Support: For warranty and technical support, contact Midnite Solar or your authorized installer. Do not attempt to repair breakers or internal busbars.