Lascar Panel Meter Applications

The vast majority of Lascar meters operate using the Dual-Slope method of conversion. Put simply, the technique involves charging a capacitor (CINT) from zero at a rate directly proportional to the input voltage and for a fixed time (see fig. 1.2). This is the integrate phase. Then the control connects the reference voltage (note that it is negative) and CINT is discharged at a rate proportional to the reference voltage. This is the reference integrate phase, the end of which is determined when the voltage on CINT is zero.

Lascar meters do not normally need special handling precautions but they do contain CMOS circuitry and static should be avoided. When soldering,use irons with earthed tips and avoid applying excessive heat to the meter’s PCB. The recommended tip diameter should be between 1 and 2mm and flat, not pointed. Large tips can transfer too much heat to the PCB and thin ones physically damage it whilst being inefficient at bridging solder across programming links.

If it is necessary to transport meters, e.g. via carrier, post, etc. then ensure that the unit is well packed. This is especially important in the case of LCD panel meters. Keep bezel materials away from the glass and do not use such packaging as ‘padded’ bags. Firm cardboard boxes should be used. Padded bags may protect against impact but not against crushing.