The breaker lock plate is used to prevent the breaker from being turned on or off.
ABB
ABB RHD XT2-XT4 F/P STAND. DIRECT
ABB AUX-C 2Q+1SY 250Vac/dc XT1...XT6 F/P
ABB Rotary-RHE XT5 Normal Transmitted
ABB XT1..XT4 Undervoltage releases 220..240Vac.
ABB RHD XT7 F/W STAND. DIRECT
ABB RHE XT1-XT3 F/P STAND. RETURNED
ABB Mechanical Interlock XT3
ABB RHD XT1-XT3 F/P STAND. DIRECT
ABB Rotary-RHD XT6 Normal Direct
ABB Front Flange-FLD XT5 F/P (Padlock)
ABB RHE XT2-XT4 F/P STAND. RETURNED
ABB E1.2..E6.2-XT7-XT7M 220..240VAC/DC Undervoltage