PMS4 - Power Management System

A better alternative to the Zig CF9, The PMS4 Power Management System from Plug-In-Systems is a combined mains 230 volt AC and 12 volt DC distribution unit, combining power and safety to give the ultimate in power management, and unlike the Zig CF9 comes with it's own Consumer Unit built-in. It is especially designed for caravan and motorhome installations, simple to install and requiring minimal attention in use.

The unit incorporates the following important features:
230v AC -
Earth leakage protection
Overcurrent protection
Reverse polarity indication

12v DC -
18 amp Transformer Charger
6 Fused outputs
Overcurrent protection
Short circuit protection
Thermal Protection

Mains Control
The PMS4 is designed to operate on a mains supply of 230 volts AC +/-10% (making it ideal for use with low continental voltages). The 40 amp RCD (Residual Current Device) gives protection against earth faults and also acts as the main isolator switch. The mains module also has three MCB's (Miniature Circuit Breakers), which are basically re-setable mains fuses, to protect against over current.

Example allocation of the MCB's are as follows:
MCB 1 (10A) - Sockets / Heater
MCB 2 (6A) - Water Heater / Lights
MCB 3 (6A) - Fridge / Battery Charger

Using in conjunction with a Generator
When using a generator in conjunction with the PMS4 the following must be observed, failure to do so may result in damage to the unit:

1. Always start the generator with the mains isolator in the vehicle turned off.
2. Allow the generator to warm up for a few minutes before energising power in the vehicle, as the output voltage can be higher when cold.
3. Check the generator output voltage regularly to ensure it is within the specification of the PMS4 system i.e. 230 volts AC +/- 10%.

Transformer / Charger
The PMS4 employs, fully automatic mains to 13.8 volt DC power supply and battery charger, able to operate with a wide range of input voltages and provide a stable output voltage even under load. The unit can provide up to 18 amps maximum, after which it will begin to shut down to protect itself.

Electrical & Thermal Protection
The battery charger is fitted with circuitry, which will protect it in the event of electrical or thermal overload. Should the current draw exceed the rated output of the unit, then it will begin to shut down. This will probably be noticed as a dimming of the 12v lighting. On removal of the excessive load the charger will automatically recover.

There is also an electronic thermal protection circuit, which will operate should the temperature of the unit rise above a safe level. If this happens then the output will shut-off until the temperature has dropped back to a safe level. This protection should only operate if the unit is not installed correctly or the venting slots have become covered.

Also fitted to the 18a model is a fan which will operate when necessary to cool the unit.

DC Fuses

Six automotive blade fuses are provided in the unit to protect all 12 volt dc circuits. Note that fuses must be replaced only with the specified values.