Hardware Manual PCD 1 / PCD 2 Series│Document 26 / 737│Edition EN 15│2008-07-22

Saia-Burgess Controls AG

Changing the battery on the PCD1 and PCD2.Mxxx CPUs

Maintenance

7

7 Maintenance

Saia® PCD1 and PCD2 components are maintenance-free, apart from some CPUs

(PCD1.M130 and PCD2.Mxxx), where the battery needs to be changed occasionally.

7.1 1 Changing the battery on the PCD1.M13x and PCD2.Mxxx CPUsChanging the battery on the PCD1.M13x and PCD2.Mxxx CPUs

When is it necessary to change the battery?

The battery voltage is monitored by the CPU. The „Battery“ LED lights up and XOB 2

is called if

 the battery voltage is below 2.4 V or above 3.5 V

 the battery is flat or shows an interrupt

 the battery is missing

In these cases, the battery should be changed. We recommend changing the

batteries with the PCD attached to the power supply, to avoid any loss of data.

CPU type Buffer Buffer time

PCD1.M110 Super Cap (soldered, maintenance-free) 30 days1)

PCD1.M120/M125 Super Cap (soldered, maintenance-free) 7 days

PCD1.M130/M135 CR 2032 lithium battery 1-3 years2)

PCD2.M110/M120

hardware version < H

2 x alkaline batteries size

LR03/AAA/AM4/Micro

1-5 years2)

PCD2.M110/M120

hardware version ≥ H

CR 2032 lithium battery 1-3 years2)

PCD2.M150/M170/M480 CR 2032 lithium battery 1-3 years2)

1) The PCD1.M110 has no hardware clock, so the buffer time is greater than it is for the PCD1.M120

2) Depending on the ambient temperature; the higher the temperature, the shorter the buffer time

i

The PCD1.M110, PCD2.M120 and PCD2.M125 CPUs have soldered-on buffer

capacitors, making them maintenance-free.

Observe the polarity of the batteries:

 For alkaline batteries, the polarity can be seen on the socket

 Insert CR 2032 coin cell in such a way that the positive pole is visible

Effect of changing the battery too late:

• all RAM contents are lost, i.e.
   Resources (registers, flags, timers, counters etc.)
   Extension memory (text/DBs ≥ 4000)
   User program, if in RAM


• die Hardware Uhr (Real Time Clock) verliert das aktuelle Datum
   The date and the hour can be written after changing the battery with the
  «SAIA Online Debug» in PG5.
  For this the following command mus be written:
  Wirte clocK dd/mm/yy hh:mm:ss [week-of-year [day-of-week]] CR