FIVE FUNCTIONS ARE PROVIDED BY THIS RELAY :

1. Measure and display of the battery voltage :

- LCD display with 4 digits and 1/2 - 20.000 points.
- Display shape :
  * for 210 V : ###.#
  * for 24/28/110 V : ###.##
- Display accuracy :
  * 16 to 70 V : +/- 0,1 V
  * 70 to 250 V : +/- 0,2 V
  * 170 to 250 V : +/- 0,5 V
- The LCD display is guaranteed in the range 0 to 70°C
- the display and the voltage and current relays should not give false data in the range between the discharge end and 30% of the nominal value.

2. Detection of the discharge end voltage:

- Voltage threshold relay, set by multi-revolution potentiometer with access by screwdriver from the box outside.
- Setting ranges :
  * 26 to 33 V : 19,5 to 30 V
  * 38 to 53 V : 34 to 52 V
  * 100 à 137 V : 84 à 131 V
  * 190 to 250 V : 150 to 243 V
- Output relay : 2 dry inverters
- Relay 1813 directly soldered on the PCB
- Relay OFF for voltage < threshold
- A LED on front face displays the relay state. This LED is in series with a NC contact.
- Escape rate < 1,12
- Threshold accuracy : +/- 0,5% of the setting.

3. Detection of the discharge beginning :

- The discharge current detection id made with a 100 mV shunt in series with the battery. The threshold is set in factory at 10 mV.
- Detection circuit holds 2 V during 1 sec.
- Output relay : 2 dry inverters
- Relay 1813 directly soldered on the PCB.
- Relay ON for U shunt > 10 mV
- A LED in front face displays the relay state. this LED is in series with a NO contact
- Escape rate < 0,8
- Threshold accuracy : +/- 0,5% of the setting
- The relay is ON after a time delay of 120 sec. (+/- 15%). Time delay modifiable in factory.
- Time delay repetitiveness : +/- 5%.

4. Auto-test :

- the relay 2481 sends a current of some mA through the shunt. Then an electronic threshold circuit permits to detect if the current checking circuit is correctly connected.
- In case of link breaking, the discharge beginning relay is ON after a time delay of 2 min.
(So the discharge beginning relay has two functions : discharge current detection and checking of the link between shunt and 2481 relay).

5. Test of the switching relays and the voltage threshold :

Relays test :
A push-button "discharge end" permits to de-energise the related relay. A push-button "discharge beginning" permits to energise the related relay.

Voltage threshold test :
2 EXT + and - terminals permit to connect a power supply equal to the 2481 range (between 50 ad 100% of the power supply setting). This power supply energises a relay which switches the measure circuits on this one. It permits to check the LCD display and the threshold (and, if necessary, its setting).