Frequently Asked Questions

1. What is the Projecta PM635J Intelli-Jay Master Charger?

Answer:

The PM635J is an integrated power management system designed for caravans and motorhomes.

It provides:

• Service battery charging from AC mains, solar and the towing vehicle.
• A built-in MPPT solar controller.
• A built-in 45A DC-DC vehicle charger.
• Starter battery maintenance charging.
• Low-voltage battery protection.
• Battery isolation and load control.
• Battery voltage, current, capacity and remaining-time monitoring.
• Support for compatible displays, wireless switches, water tank probes and monitoring accessories.

The PM635J is a fixed electrical system. AC mains and vehicle wiring must be completed by a suitably qualified installer.

2. Which charging sources can the PM635J use at the same time?

Answer:

The PM635J can receive charging power from:

• AC mains.
• Solar panels.
• The towing vehicle.

The charging priority is:

• AC mains and solar: Both sources can operate together.
• AC mains and vehicle DC: AC mains takes priority.
• Solar and vehicle DC: Both sources can operate together.

The AUX or Solar LED may flash slowly when that charging source is available but AC mains is currently charging the battery.

Connecting AC mains or solar while the charger is in Float mode may cause the charger to return to Bulk charging.

3. Which battery types are supported by the PM635J?

Answer:

The PM635J supports the following 12V battery profiles:

• WET or flooded lead-acid.
• AGM.
• GEL.
• LFP or LiFePO4 lithium.

The battery type and battery capacity should be selected using the connected display or app where available.

For lithium batteries, the charging current is controlled according to the configured battery capacity. The manual specifies a maximum lithium charging current of approximately 30% of the battery capacity.

Always confirm that the battery manufacturer permits the selected charging voltage and current.

4. How do I set the battery type and charging current?

Answer:

The preferred method is to configure the battery type, capacity and charging current through the connected display or app.

The most recently used configuration method overrides the previous setting.

Battery type using DIP switches 3 and 4

• WET: Switch 3 ON and Switch 4 ON.
• LFP: Switch 3 ON and Switch 4 OFF.
• GEL: Switch 3 OFF and Switch 4 ON.
• AGM: Switch 3 OFF and Switch 4 OFF.

Lead-acid charging current using DIP switches 1 and 2

• Switch 1 ON and Switch 2 ON: 15A AC and 30A solar.
• Switch 1 ON and Switch 2 OFF: 30A AC and 45A solar.
• Switch 1 OFF and Switch 2 ON: 45A AC and 45A solar.
• Switch 1 OFF and Switch 2 OFF: 60A AC and 45A solar.

For the lithium profile, the DIP-switch information lists 60A AC and 45A solar charging. However, capacity-based configuration through the display or app is preferred.

Confirm the battery chemistry, capacity and permitted charging current before changing any settings.

5. What do the PM635J charging stages mean?

Answer:

The PM635J uses several charging stages:

Soft Start
The charger begins charging the battery gradually.

Bulk
The charger supplies higher current to raise the battery state of charge quickly.

Absorption
The charger maintains a controlled voltage while completing the charge.

Float
The battery is fully charged and is maintained at a safe voltage.

Recycle
The charger periodically checks and refreshes the battery condition.

CHG LED indications

• Solid green: Battery is in Float mode.
• Slow flash approximately once per second: Bulk, Absorption or starter-battery/VSR charging.
• Quick flash approximately twice per second: Battery is discharging.
• Off: Battery is disconnected.

6. Does the PM635J charge the vehicle starter battery?

Answer:

Yes. The PM635J can provide up to approximately 3A of maintenance charging to the vehicle starter battery when AC mains or solar charging is available.

If the starter battery voltage is below approximately 12.4V, maintenance charging may begin after a delay of around 30 minutes.

Charging stops when the starter battery reaches approximately 12.8V.

The AUX LED may indicate that starter-battery charging is active or that vehicle input is available while AC mains has priority.

7. How does the vehicle DC-DC charger operate?

Answer:

The PM635J includes a built-in 45A DC-DC charger.

Standard alternator operation

Charging normally starts when the vehicle battery reaches approximately 12.8V for around four seconds.

Charging stops when the vehicle battery falls below approximately 12.0V for around five seconds.

Smart alternator operation

When a D+ or ignition signal is connected, charging can begin at approximately 12.2V.

Charging continues until the alternator is switched off or the voltage falls below the applicable turn-off threshold.

The D+ connection may use pin 12 of a suitable trailer connector or an approved ignition circuit.

Vehicle and D+ wiring must be completed by a qualified auto electrician.

8. What solar input can be connected to the PM635J?

Answer:

The PM635J has a built-in MPPT solar controller.

The solar input limits are:

• Maximum solar open-circuit voltage: 42V DC.
• Maximum solar charging current: 45A.
• Maximum solar supply current: 45A.
• Maximum total solar panel capacity: 1000W.

The solar array’s open-circuit voltage must remain below 42V, including during cold weather when panel voltage may increase.

Solar system design and installation should be confirmed by a qualified installer.

9. How does low-voltage battery protection work?

Answer:

The PM635J can automatically disconnect controlled loads when the house battery voltage becomes too low.

Default lead-acid settings

• Disconnect voltage: approximately 10.5V.
• Reconnect voltage: approximately 11.5V.

Default LFP lithium settings

• Disconnect voltage: approximately 11.2V.
• Reconnect voltage: approximately 12.2V.

Once the battery voltage falls below the configured threshold, controlled loads are disconnected after the programmed delay.

The loads reconnect once the battery voltage recovers above the reconnect threshold.

Permanent loads or loads connected directly to the battery may remain powered even when the PM635J-controlled loads are switched off.

10. How do the manual battery switch and remote switch work?

Answer:

Manual switch

The side-mounted manual switch should be set to ON for normal operation and battery charging.

When AC mains is connected but the manual switch is OFF, the display and charging system may also remain off.

The manual switch must be ON before the remote switch can operate.

Remote switch

The remote switch connects to the two remote-switch terminals near the Type 3 connector.

When no remote switch is installed, the two remote-switch terminals must be bridged.

The remote switch operates in a similar way to the side-mounted manual switch.

For storage, the manual or remote switch can be turned off to reduce battery drain. Permanent or direct-to-battery loads may still remain active.

11. Why can the battery monitor show an inaccurate state of charge?

Answer:

The PM635J calculates battery state of charge using measured charging and discharging current.

Loads connected directly to the battery and outside the PM635J measurement path may not be included in the calculation. This can cause inaccurate battery percentage, remaining-capacity or time-remaining readings.

Check the following:

1. Confirm that normal loads are connected through the PM635J where intended.
2. Identify any heavy loads connected directly to the battery.
3. Confirm that a compatible shunt is installed where required.
4. Check that the configured battery type and capacity are correct.
5. Fully charge the battery from AC mains until the CHG LED is solid or the display shows Float.

After replacing the battery, complete the recommended calibration process by discharging the battery below the return-to-bulk voltage and then fully charging it from AC mains.

12. What does Night Mode do?

Answer:

When Night Mode is activated:

• The display backlight turns off.
• The cooling fans operate at a reduced speed.
• Charging current is reduced to approximately half of the selected charging rate.

Battery charging may take longer while Night Mode is active.

13. What maintenance is recommended for the battery monitor?

Answer:

To help maintain accurate battery monitoring:

1. Fully charge the battery from AC mains approximately every two weeks.
2. Fully charge the battery from AC mains at least once every three months, including during storage.
3. Continue charging until the CHG LED is solid or the display indicates Float.
4. Confirm the PM635J power switch is ON during AC charging.
5. Confirm the house battery is a nominal 12V battery.
6. Maintain at least 50mm of ventilation clearance on each side of the PM635J.
7. Complete a full AC charge after replacing the battery.

Charging from AC mains is recommended for calibration because solar availability and connected loads can vary.

14. How do I pair a wireless switch panel with the PM635J?

Answer:

Follow these steps:

1. Open Engineering Settings on the connected display.
2. Enter the engineering password shown in the manual: 1999.
3. Open Channel Pairing.
4. Select the plus symbol.
5. Press any button on the wireless panel twice slowly.
6. Select the on-screen button corresponding to the key being configured.
7. Select the function you want to assign.
8. Repeat the process for each required button.
9. Select Confirm.
10. Select OK when the configuration-complete message appears.

Keep the wireless panel close to the display during pairing and press the buttons slowly and deliberately.

15. Which water tank probes are compatible with the PM635J?

Answer:

The PM635J supports the following water tank probes:

PMWS200

• Side installation.
• Suitable for tanks with a depth greater than approximately 200mm.

PMWS400

• Side installation.
• Suitable for tanks approximately 300mm to 400mm deep.

Confirm the tank depth, probe length and mounting arrangement before ordering or installing the probe.

16. What ventilation clearance is required around the PM635J?

Answer:

Maintain at least 50mm of clear space on each side of the PM635J.

The unit must be installed where air can circulate freely.

Do not:

• Cover the cooling openings.
• Block the ventilation slots.
• Install the unit immediately beside heat-producing equipment.
• Continue using the system if the enclosure becomes excessively hot.

Restricted airflow may cause overtemperature faults.

17. How do the PM635J output categories work?

Answer:

The PM635J uses different output categories.

Class A5

Relay-controlled and fused outputs protected by the main switching arrangement.

Typical applications include:

• Water pump.
• Hot-water system.
• Television.

Class C2

Fused outputs controlled through the main switch relay.

Typical applications include ventilation fans and similar loads.

Class D

Permanent-on outputs.

Typical applications include:

• Refrigerator.
• Breakaway system.
• Sway controller.
• Radio memory.

Class D or direct-to-battery loads may remain powered when the main battery switch or LOAD control is off.

18. Why will the awning or slide-out not operate while connected to the towing vehicle?

Answer:

The PM635J can prevent the awning or slide-out from operating while the towing vehicle is connected.

To operate the awning or slide-out:

1. Park the caravan safely.
2. Disconnect the caravan from the towing vehicle.
3. Turn the applicable load switch on.
4. Confirm there are no active fuse or fault indications.
5. Operate the awning or slide-out.

Keep people and objects clear of the awning or slide-out travel area.

Troubleshooting Questions and Answers

The PM635J LED indicators and fault-flash patterns can be used as the starting point for troubleshooting.

1. Why does the PM635J have no display, no output or no AC charging?

Answer:

Check the following:

1. Confirm the side-mounted PM635J power switch is ON.
2. Confirm AC mains is connected.
3. Check whether the Mains LED is illuminated.
4. If a remote switch is installed, confirm it is ON.
5. If no remote switch is installed, confirm the two remote-switch terminals are bridged.
6. Check whether the red Fault LED or Fuse indicator is illuminated or flashing.
7. Confirm the house battery is connected with the correct polarity.
8. Confirm the house battery is not below the low-voltage disconnect threshold.

Arrange qualified inspection when:

• AC mains is available but the Mains LED remains off.
• The fault returns after connected loads are removed.
• Wiring or connectors are hot or damaged.
• There is a burning smell or evidence of overheating.

Disconnect AC mains before carrying out external visual checks. Do not open the PM635J enclosure.

2. Why is the Mains LED flashing quickly?

Answer:

A quickly flashing Mains LED indicates that the AC input is abnormal or outside the expected operating condition.

Follow these steps:

1. Disconnect the PM635J from AC mains.
2. Check the external power outlet, plug and lead for visible damage.
3. Check whether an upstream circuit breaker, safety switch or protection device has tripped.
4. Reconnect the system to a known suitable 230–240V AC supply.
5. Check the Mains LED again.

Stop using AC charging and arrange qualified inspection if the LED continues to flash quickly.

Do not test or repair fixed 240V wiring unless licensed and qualified.

3. Why is the AUX LED flashing quickly?

Answer:

A quickly flashing AUX LED indicates a vehicle battery input error.

The voltage, polarity, connection or D+ signal may not be suitable for normal charging.

Follow these steps:

1. Disconnect the caravan from the towing vehicle.
2. Inspect the trailer plug and socket.
3. Check for loose, damaged or corroded connections.
4. Confirm the vehicle battery and alternator are operating normally.
5. Confirm the D+ or ignition wiring is correct where fitted.
6. Reconnect the caravan.
7. Check whether the AUX LED changes to solid ON or slow flashing.

Have the system inspected by a qualified auto electrician if the AUX LED continues to flash quickly or the vehicle charging wiring becomes hot.

4. Why is the Solar LED flashing quickly?

Answer:

A quickly flashing Solar LED indicates an abnormal solar input.

Follow these steps:

1. Isolate the solar input using the approved isolation method.
2. Check for loose, reversed, damaged or corroded solar connections.
3. Confirm the solar-array open-circuit voltage does not exceed 42V DC.
4. Reconnect the solar input.
5. Check whether the Solar LED returns to normal operation.

Solar panels may remain electrically live during daylight even when the battery is disconnected. Use a qualified technician where wiring access or electrical testing is required.

5. Why is the Fuse indicator continuously illuminated?

Answer:

A solid Fuse indicator normally means that a fuse has blown.

Follow these steps:

1. Turn off the affected load.
2. Inspect the connected appliance and cable.
3. Check for a short circuit, damaged wiring or excessive current draw.
4. Correct the cause of the fault.
5. Replace the fuse with the correct type and rating.
6. Turn the load back on.
7. Confirm the Fuse indicator remains off.

Never replace the fuse with a higher-rated fuse. A higher fuse rating can damage the wiring and create a fire risk.

6. Why is the red Fault LED continuously illuminated?

Answer:

A solid red Fault LED indicates a short circuit.

Follow these steps:

1. Turn the load switch off.
2. Disconnect recently added or suspect loads.
3. Inspect load wiring and connectors.
4. Check for pinched insulation, moisture, damage or reversed polarity.
5. Correct the fault before switching the load back on.
6. If the Fault LED remains illuminated with the loads disconnected, arrange qualified inspection.

Do not repeatedly reset a short-circuit fault. Repeated resets may overheat the wiring or damage the PM635J.

7. What does one flash of the red Fault LED mean?

Answer:

One flash indicates house battery undervoltage.

Follow these steps:

1. Turn off unnecessary electrical loads.
2. Connect AC mains or another suitable charging source.
3. Allow the battery to charge above the reconnect threshold.
4. Check whether the loads automatically reconnect.
5. Check the battery condition if the voltage falls again quickly.

Default lead-acid thresholds

• Disconnect: approximately 10.5V.
• Reconnect: approximately 11.5V.

Default lithium thresholds

• Disconnect: approximately 11.2V.
• Reconnect: approximately 12.2V.

Arrange battery testing if the fault returns with minimal load or if the battery will not accept or retain charge.

Stop using the battery if it is swollen, hot, leaking or physically damaged.

8. What do two flashes of the red Fault LED mean?

Answer:

Two flashes indicate house battery overvoltage.

Follow these steps:

1. Turn off or disconnect external charging sources where safe.
2. Do not continue charging the battery.
3. Confirm the selected battery type matches the installed battery.
4. Arrange qualified testing of the AC charger, solar input and vehicle charging input.

Keep people clear and follow the battery manufacturer’s emergency procedure if the battery is hot, swollen, venting, damaged or producing an unusual smell.

9. What do three, eight or nine flashes of the red Fault LED mean?

Answer:

These patterns indicate an overtemperature condition.

• Three flashes: Heatsink overtemperature.
• Eight flashes: PM635J unit overtemperature.
• Nine flashes: PCB or load-circuit overtemperature.

Follow these steps:

1. Stop charging or turn the load switch off.
2. Disconnect high-current loads.
3. Check that there is at least 50mm clearance on each side of the PM635J.
4. Confirm the ventilation openings are not blocked.
5. Allow the PM635J to cool.
6. Restart the system only after it has cooled.
7. Arrange inspection if the fault returns.

Do not continue using the system if the enclosure, cables or connectors remain excessively hot.

10. What do four flashes of the red Fault LED mean?

Answer:

Four flashes indicate a Bulk charge timeout.

The battery has remained in Bulk charging longer than expected.

Follow these steps:

1. Turn off non-essential loads that may be consuming charging current.
2. Check the battery terminals for looseness or corrosion.
3. Check the charging cables for excessive voltage drop.
4. Confirm the selected battery type is correct.
5. Confirm the configured battery capacity is correct.
6. Disconnect and reconnect the charging source to restart charging.
7. Test the battery if the fault returns.

Arrange technical inspection if the battery cannot progress beyond Bulk charging after loads and connections have been checked.

11. What do five flashes of the red Fault LED mean?

Answer:

Five flashes indicate a VSR or vehicle charging system abnormality.

Follow these steps:

1. Restart the PM635J using the manual power switch.
2. Disconnect the caravan from the towing vehicle.
3. Reconnect the towing-vehicle input.
4. Inspect the trailer connector.
5. Check the vehicle battery.
6. Check the D+ or ignition signal where fitted.
7. Arrange inspection by a qualified auto electrician if the fault returns.

Do not bypass the vehicle charging protection or install an unapproved jumper to force charging.

12. Why does the PM635J remote battery switch not work?

Answer:

Follow these steps:

1. Confirm the side-mounted manual power switch is ON.
2. Inspect the remote-switch wiring.
3. Confirm the wiring is connected to the correct two terminals near the Type 3 connector.
4. Confirm the remote switch provides the required open-and-closed contact.
5. If no remote switch is installed, confirm the two terminals are bridged.
6. Inspect the bridge and connector for looseness or damage.

Arrange technical inspection if the wiring is correct but the remote switch still does not control the PM635J.

13. Why does DC-DC charging not start when the towing vehicle is running?

Answer:

Follow these steps:

1. Start the towing vehicle.
2. Allow the vehicle battery voltage to stabilise.
3. Check the AUX LED.
4. A quickly flashing AUX LED indicates a vehicle-input error.
5. Confirm the trailer connector is fully connected.
6. Inspect the vehicle charging cable and connections.
7. For a smart alternator, confirm the D+ or ignition signal is active.
8. Confirm the vehicle battery reaches the applicable charging start voltage.
9. Have voltage drop, polarity and cable capacity checked by a qualified auto electrician.

When charging is active, the AUX LED should normally illuminate.

The AUX LED may flash slowly when vehicle input is available but AC mains is taking priority.

14. Why is the displayed battery percentage or time remaining inaccurate?

Answer:

Follow these steps:

1. Confirm the selected battery type matches the installed battery.
2. Confirm the battery capacity setting is correct.
3. Identify any loads connected directly to the battery.
4. Confirm all relevant charging and discharging current passes through the intended measurement path.
5. Install or inspect the compatible shunt where required.
6. Fully charge the battery from AC mains.
7. Continue charging until the CHG LED is solid or the display indicates Float.
8. After replacing the battery, complete the recommended calibration cycle.

Battery voltage alone cannot provide an accurate state-of-charge reading while the battery is charging or supplying a load.

15. Why will the wireless switch panel not pair?

Answer:

Follow these steps:

1. Confirm the wireless panel battery is installed.
2. Replace or test the panel battery if necessary.
3. Move the wireless panel closer to the display.
4. Open Engineering Settings.
5. Open Channel Pairing.
6. Select the plus symbol.
7. Press a wireless panel button twice slowly.
8. Assign the required function.
9. Select Confirm.
10. Repeat the process for each key.
11. Select OK when pairing is complete.

If the display does not detect any button presses, try a known-good wireless panel battery and confirm that the panel and display are compatible.

16. Why does the awning or slide-out remain inactive?

Answer:

Follow these steps:

1. Park the caravan safely.
2. Disconnect the caravan from the towing vehicle.
3. Turn the applicable load switch on.
4. Check for an illuminated Fuse indicator.
5. Check for a red Fault LED or fault-flash pattern.
6. Confirm the awning or slide-out controller is receiving power.
7. Arrange wiring and control-system inspection if the output remains inactive.

Keep people and objects clear of the awning or slide-out before testing operation.

Safety Warnings

• Disconnect AC mains before connecting or disconnecting the battery.
• Do not work on fixed 240V wiring unless licensed and qualified.
• Do not replace a fuse with a higher rating.
• Solar panels may remain electrically live during daylight.
• Keep PM635J ventilation openings clear.
• Stop using the system if there is smoke, a burning smell, melted wiring, damaged connectors or repeated overtemperature faults.
• Stop using a battery that is swollen, excessively hot, leaking, venting or physically damaged.

When to Contact Projecta Technical Support

Contact Projecta Technical Support when the fault remains after completing the relevant checks or when qualified electrical testing is required.

Provide:

• Product model: PM635J.
• Battery type and capacity.
• Measured battery voltage.
• Charging sources connected.
• LED status or fault-flash count.
• Photos of the unit, display, wiring and connectors.
• Details of when the problem occurs.
• Whether the issue can be repeated.
• Proof of purchase where a warranty assessment may be required.

Projecta Technical Support: 1800 422 422.